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Cadmium Telluride
CdTe thin-film technology is being actively commercialized. CdTe cell efficiencies are over 16% in the laboratory; commercial module efficiencies are likely to be in the 9% range in the first manufacturing plants. Companies have an array of inexpensive options to choose from in CdTe fabrication-there are more than a dozen ways to make 10%—efficient cells.
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Back to Top Conference Papers
| Post Date | 10/29/2008 |
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| Title | MEASURING CDS/CDTE BACK CONTACT BARRIER HEIGHTS BY INTERNAL PHOTOEMISSION |
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| Link | (PDF 959 KB) Download Acrobat Reader. |
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| Author | A. Fahrenbruch |
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| Description | The back contact of the CdS/CdTe solar cell is one of the most critical aspects in optimizing efficiency and stability. A fundamental parameter is the barrier height ?bc and its measurement is important to fully understanding the device.
Plotting the Internal photoemission (IPE) current response to sub-band-gap light according to the Fowler theory gives an intercept equal to the barrier height. IPE can be applied to completed cells, and to thick, thin, and n/i/p cells. Results are compared for a number of cells from various fabricators, including those with good and bad contacts and electronically thick and thin cells. Results suggest two barriers in parallel: a high one, (~ 0.9 eV) which agrees well with the observed UPS values and a low one (~ 0.3 eV) with a much smaller area fraction (1 - 4%) which dominates the contact transport and corresponds more closely to the values observed for efficient cells. For thick cells, IPE results agree well with thermal measurements. |
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| Venue | 33rd IEEE PV Specialists Conference, San Diego, CA, May 12-16, 2008 |
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| Source | Colorado State University |
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| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 07/2008 |
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| Post Date | 10/29/2008 |
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| Title | EXPLORING BACK CONTACT TECHNOLOGY TO INCREASE CDS/CDTE SOLAR CELL EFFICIENCY |
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| Link | (PDF 237 KB) Download Acrobat Reader. |
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| Author | A. Fahrenbruch |
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| Description | The primary routes for increasing CdS/CdTe solar cell efficiency involve increasing free carrier density, reducing bulk and interface recombination, and/or reducing back contact barrier height ?bc. This paper focuses on the role of the back contact barrier in increasing cell efficiency. Measurement of ?bc and back surface recombination are outlined and three CdTe/MX/M back contact prototypes, each with particular strengths, are discussed. |
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| Venue | Materials Research Society Spring Meeting, San Francisco, CA, 4/9-13, 2007, (MRS Smposia Proc vol 1012, p 283) |
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| Source | Colorado State University |
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| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 07/2008 |
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| Post Date | 05/30/2008 |
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| Title | THE ROLE OF POLYCRYSTALLINE THIN-FILM PV TECHNOLOGIES IN COMPETITIVE PV MODULE MARKETS |
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| Link | (PDF 351 KB) Download Acrobat Reader. |
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| Authors | B. Von Roedern, H. S. Ullal |
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| Description | This paper discusses the developments in thin-film PV technologies. It provides an outlook on future commercial module efficiencies achievable based on today?s knowledge about champion cell performance. It also provides a relative cost comparison of thin-film and wafer/ribbon based Si PV modules. In 2007, about 65% of the modules produced in the US were thin-film modules when amorphous silicon modules are also considered. |
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| Venue | Presented at the 33rd IEEE PVSC Conference, San Diego, CA 05/12-16/2008 |
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| Source | National Renewable Energy Laboratory |
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| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 05/2008 |
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| Post Date | 09/28/2007 |
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| Title | THIN FILM CIGS AND CDTE PHOTOVOLTAIC TECHNOLOGIES: COMMERCIALIZATION, CRITICAL ISSUES, AND APPLICATIONS |
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| Link | (PDF 725 KB) Download Acrobat Reader. |
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| Authors | H. S. Ullal, B. Von Roedern |
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| Description | We report here on the major commercialization aspects of thin-film photovoltaic (PV) technologies based on CIGS and CdTe (a-Si and thin-Si are also reported for completeness on the status of thin-film PV). Worldwide silicon (Si) based PV technologies continues to dominate at more than 94% of the market share, with the share of thin-film PV at less than 6%. However, the market share for thin-film PV in the United States continues to grow rapidly over the past several years and in CY 2006, they had a substantial contribution of about 44%, compared to less than 10% in CY 2003. In CY 2007, thin-film PV market share is expected to surpass that of Si technology in the United States. Worldwide estimated projections for CY 2010 are that thin-film PV production capacity will be more than 3700 MW. A 40-MW thin-film CdTe solar field is currently being installed in Saxony, Germany, and will be completed in early CY 2009. The total project cost is Euro 130 million, which equates to an installed PV system price of Euro 3.25/-watt averaged over the entire solar project. This is the lowest price for any installed PV system in the world today. Critical research, development, and technology issues for thin-film CIGS and CdTe are also elucidated in this paper. |
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| Venue | 22nd EC PVSEC, Milano, Italy Sep 3-7, 2007, paper presented |
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| Source | National Renewable Energy Laboratory |
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| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 09/2007 |
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| Post Date | 04/30/2007 |
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| Title | OUTDOOR MONITORING AND HIGH VOLTAGE BIAS TESTING OF THIN FILM PV MODULES |
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| Link | (MS Word 64 KB) |
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| Author | N. G. Dhere |
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| Description | Limitations of accelerated testing to predict all possible degradation modes and mechanisms in the photovoltaic PV modules necessitate that actual outdoor monitoring and testing of PV modules be performed out-doors. For this reason, thin film PV modules from leading US thin film PV manufacturers namely, First Solar (Glass/CdTe/Glass), Shell Solar Glass/CIS/Glass), Shell Solar New (Glass/CIGS/Glass), United Solar (a-Si:H on flexible substrate), Energy Photovoltaics (Glass/a-Si:H/Glass) and Global Solar (CIS on flexible substrate) with additional one crystalline silicon module are being tested. The goal is to assess their performance in the hot and humid climate of Florida and to correlate the PV performance with the meteorological parameters namely, solar irradiance, temperature, relative humidity, wind speed, etc. Statistical data analysis of the recorded data is carried out on a daily basis and on a monthly basis with PVUSA type regression analysis. Current-voltage characteristics (I-V) of module arrays taken on a regular basis complement the results obtained with continuous data monitoring. Moreover, high voltage bias testing of the modules is carried out to study behavior of leakage currents and detect any packaging material and processing flaws and consequently the module reliability. |
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| Venue | DOE Solar Technology Review Meeting, Denver, CO, 4/17-19/2007 |
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| Source | FLorida Solar Energy Center |
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| Document Type | Conference Papers (Word document) |
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| Resource Date | 03/2007 |
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| Post Date | 04/30/2007 |
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| Title |   VOLTAGE DEFICIT IN THIN-FILM POLYCRYSTALLINE SOLAR CELLS |
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| Link | (MS Word 46 KB) |
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| Author | J. R. Sites |
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| Description | The highest reported efficiency for thin-film CIGS solar cells is 3% larger than the highest seen with CdTe cells. The lower CdTe efficiency is the result of a much larger voltage deficit between CdTe cells and crystalline cells of similar band gap. The explanation for the difference is that CIGS has a natural energy barrier, which repels holes from grain boundaries, but CdTe does not. Significant efficiency increases in CdTe cells will therefore likely require new structures with full absorber depletion and electron reflection at the back contact. |
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| Venue | DOE Solar Technology Review Meeting, Denver, CO 4/17-17/2007 |
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| Source | Colorado State University |
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| Document Type | Conference Papers (Word document) |
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| Resource Date | 03/2007 |
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| Post Date | 10/26/2006 |
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| Title | BOS COST SAVINGS NEEDS AND POTENTIAL FOR LARGE SCALE GROUND BASED PV SYSTEMS UNTIL 2010 |
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| Link | (PDF 495 KB) Download Acrobat Reader. |
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| Author | M. Bachler |
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| Description | More and more large scale ground based systems were implemented with thin-film modules in the past years in Germany. Based on module pricing thin film modules appear to be very attractive for this type of application. However there are quite significant differences in balance-of-system (BOS) costs within different c-Si and thin film (TF) module types, which have a high impact on total system costs. The BOS cost portion is significantly higher for systems with TF modules compared to c-Si modules. Existing c-Si modules and BOS components were developed and optimized to achieve cost savings in the past decades already a lot. TF modules as well as the related BOS components are at the very beginning of this development so the cost saving potential ? especially for BOS costs is considered to be significantly higher for TF module based systems. Since a 6.5% degression in the feed-in tariff is required in the German EEG for ground based systems a high cost reduction pressure is imposed on total system costs. The results of BOS cost savings achieved already will be demonstrated for a sample thin-film module. |
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| Venue | Dresden World Conference |
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| Source | Phonix SonnenStrom AG |
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| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 09/2006 |
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| Post Date | 06/14/2006 |
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| Title | CDTE PHOTOVOLTAICS: LIFE CYCLE ENVIRONMENTAL PROFILE AND COMPARISONS |
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| Link | (PDF 210 KB) Download Acrobat Reader. |
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| Author | V. Fthenakis |
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| Description | We discuss the emissions of cadmium throughout all the life stages of CdTe PV modules, from extracting, refining, and purifying the raw materials to producing, using, and disposing or recycling of the modules. Then, we compare these emissions with those in the life cycle of three different types of crystalline Si PV modules. The energy requirement and energy pay back times (EPBT) of CdTe PV modules is considerably shorter than that of crystalline Si modules, although the latter exhibit higher efficiencies. This difference is primarily due to the energy used to process silicon, a fraction of which is derived from fossil fuels, inevitably producing Cd and many other heavy-metal emissions. |
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| Venue | Presented at the European Material Research Society Meeting |
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| Source | N/A |
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| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 06/2006 |
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| Post Date | 08/25/2006 |
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| Title | POLYCRYSTALLINE THIN-FILM PHOTOVOLTAICS: FROM THE LABORATORY TO SOLAR FIELDS |
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| Link | (PDF 682 KB) Download Acrobat Reader. |
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| Authors | B. Von Roedern, H. S. Ullal, K. Zweibel |
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| Description | We review the status of commercial polycrystalline thin-film solar cells and photovoltaic (PV) modules, including current and projected commercialization activities. Major technical progress has occurred in the area of thin-film PV technologies, particularly those based on cadmium telluride (CdTe) and copper indium diselenide (CuInGaSe2) |
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| Venue | Presented at the 2006 IEEE 4th World Conference on Photovoltaic Energy Conversion (WCPEC-4) Waikoloa, Hawaii May 7?12, 2006
Conference Paper NREL/CP-520-39838 May 2006 |
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| Source | National Renewable Energy Laboratory |
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| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 05/2006 |
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| Post Date | 05/18/2006 |
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| Title | HIGH-EFFICIENCY CDTE AND CIGS THIN-FILM SOLAR CELLS: HIGHLIGHTS AND CHALLENGES |
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| Link | (MS Word 602 KB) |
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| Authors | R. Noufi, K. Zweibel |
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| Description | Thin-film photovoltaic (PV) modules of CdTe and Cu(In,Ga)Se2 (CIGS) have the potential to reach cost-effective PV-generated electricity. These technologies have transitioned from the laboratory to the market place. Pilot production and first-time manufacturing are ramping up to higher capacity and enjoying a flood of venture-capital funding. CIGS solar cells and modules have achieved 19.5% and 13% efficiencies, respectively. Likewise, CdTe cells and modules have reached 16.5% and 10.2% efficiencies, respectively. Even higher efficiencies from the laboratory and from the manufacturing line are only a matter of time. Manufacturing-line yield continues to improve and is surpassing 85%. Long-term stability has been demonstrated for both technologies; however, some failures in the field have also been observed, emphasizing the critical need for understanding degradation mechanisms and packaging options. These two thin-film technologies have a common device/module structure: substrate, base electrode, absorber, junction layer, top electrode, patterning steps for monolithic integration, and encapsulation. The monolithic integration of thin-film solar cells can lead to significant manufacturing cost reduction compared to crystalline Si technology. The CdTe and CIGS modules share common structural elements. In principle, this commonality should lead to similar manufacturing cost per unit area, and thus, the module efficiency becomes the discriminating factor that determines the cost per watt. The long-term potential of the two technologies require R&D emphasis on science and engineering-based challenges to find solutions to achieve targeted cost-effective module performance, and in-field durability. Some of the challenges are common to both, e.g., in-situ process control and diagnostics, thinner absorber, understanding degradation mechanisms, protection from water vapor, and innovation in high-speed processing and module design. Other topics are specific to the technology, such as lower-cost and fast-deposition processes for CIGS, and improved back contact and voltage for CdTe devices. |
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| Venue | WPEC4, Hawaii |
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| Source | National Renewable Energy Laboratory |
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| Document Type | Conference Papers (Word document) |
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| Resource Date | 05/2006 |
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| Post Date | 05/22/2006 |
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| Title | TECHNOLOGY CHOICE AND THE COST REDUCTION POTENTIAL OF PHOTOVOLTAICS |
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| Link | (PDF 116 KB) Download Acrobat Reader. |
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| Authors | J. E. Trancik, K. Zweibel |
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| Description | We use a combination of system component analyses and individual experience curves for crystalline silicon (x-Si) modules, thin-film (TF) modules, and the balance of system (BOS) components, to compare future growth scenarios for photovoltaics (PV). The growth rates of TF and x-Si technologies are varied, while overall PV growth is held constant at 30%. For each of these scenarios, we estimate the total investment required for PV to reach a break-even point with fossil fuel based generation; and we investigate the intrinsic/lowest achievable costs from an analysis of potential materials, processing, and efficiency improvements. Our results show that a high growth rate (50 to 70% per year) of new technologies with low intrinsic costs could decrease the total investment required to reach break-even by up to 70 billion USD, as compared to a scenario where x-Si continues to dominate the market. Furthermore, the system component analysis indicates that existing TF modules can reach the low cost levels assumed in the experience curve model. These results suggest that the future growth of photovoltaics (PV) is dependent on which PV technologies grow most rapidly. New, low intrinsic cost technologies that are successfully able to enter the market could dramatically increase the potential for PV to become a globally significant energy conversion technology within the next two decades. |
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| Venue | Trancik and Zweibel, WCPEC-4 2006 |
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| Sources | National Renewable Energy Laboratory; Santa Fe Institute |
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| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 05/2006 |
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| Post Date | 09/19/2006 |
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| Title | HOW CDTE SOLAR CELLS OPERATE: DETERMINING COLLECTION USING BIFACIAL DEVICE CHARACTERIZATION |
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| Link | (PDF 113 KB) Download Acrobat Reader. |
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| Authors | D. Desai, S. S. Hegedus, B. E. McCandless, R. W. Birkmire, K. D. Dobson, D. Ryan |
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| Description |
The results presented in this paper provide a quantitative understanding of minority carrier transport parameters in CdTe based photovoltaic devices. We have demonstrated that bifacial device characterization is a valuable and efficient tool for analysis of the primary transport parameters and allows separation of the primary CdS/CdTe junction from the back contact. We conclude that for standard front illumination, the fill factor (FF) and spectral response from front (SR F) are limited by voltage dependent collection and L is nearly irrelevant. However, spectral response from back illumination (SRB) is limited by diffusion through the bulk to the depletion edge. W and L were derived by extensive numerical analysis of SRB data. The values of W obtained were independently confirmed by CV measurements, thus validating the numerical model and the analysis procedure. The blocking contact usually observed in CdTe devices is photoconductive and can be effectively eliminated by illumination. This blocking contact barrier has no effect on Voc. |
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| Venue | IEC, U. Delaware, paper given at 4th WCPEC (Hawaii, 2006) |
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| Source | University of Delaware |
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| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 05/2006 |
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| Post Date | 11/07/2006 |
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| Title | THE RELATIONSHIP OF CDS/CDTE CELL BAND PROFILES TO J-V CHARACTERISTICS AND BIAS-DEPENDENT QUANTUM EFFICIENCY |
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| Link | (PDF 1.6 MB) Download Acrobat Reader. |
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| Author | A. Fahrenbruch |
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| Description |
AMPS models of two extreme profiles are discussed here as illustrations: an n/i/p junction, where V bi is mainly supported by charge at the contacts, and an n/p junction, where Vbi is supported by charge in the bulk CdTe within the absorber
There are several general pathways to increasing the efficiency of CdS/CdTe cells. Since J sc is close to its limit, those with the most potential yield involve increasing the cell voltage at the maximum power point (Vmax). These are discussed here in a theoretical way to view trends, allowing that they may be very difficult or impossible to realize in practice. One pathway is by increasing the net negative charge in the CdTe by ?p-type doping.? Another is by increasing the minority carrier lifetime (tn) by, for example, control of impurities, reducing growth rate, and/or changing the micro-stoichiometry. These two pathways deal with bulk materials properties. A third pathway is by decreasing the back-contact barrier height Fbc and the recombination there, both interface properties. Many other pathways are less risky and more practical including: thinner windows and/or absorber layers, increasing the window band gap, and optical optimization.
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| Venue | 4th WCPEC ((IEEE PVSC), Hawaii 05/2006 paper |
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| Source | Colorado State University |
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| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 05/2006 |
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| Post Date | 10/20/2005 |
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| Title | A REVIEW OF RISKS IN THE SOLAR ELECTRIC LIFE-CYCLE |
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| Link | (PDF 642 KB) Download Acrobat Reader. |
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| Authors | V. Fthenakis, H. C. Kim |
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| Description | Early studies of risks in the life cycle of solar electric technologies do not represent their current stage of development. Our study updates the data used in previous studies and also accounts for the full life-cycle of photovoltaics. We show that the non-radiological risks of the solar electric- and nuclear-life cycles are approximately equal. This contradicts the conclusions of some earlier studies according to which the former presented much greater occupational and public non-radiological risks than the latter. |
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| Venue | Brussels 2005 |
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| Source | Brookhaven National Laboratory |
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| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 10/2005 |
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| Post Date | 10/20/2005 |
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| Title | LIFE CYCLE ANALYSIS OF PHOTOVOLTAIC SYSTEMS |
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| Link | (PDF 144 KB) Download Acrobat Reader. |
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| Author | V. Fthenakis |
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| Description | Life Cycle Analyses (LCA) at BNL show that: i) The BOS of an optimized installation has an energy payback time (EPBT) of only 0.4 years for average US insolation, which is 70% lower than previously reported estimates. ii) The EPBT of CdTe modules produced and used in the U.S. is 0.85 years. iii) The life-cycle CO2 emissions of the nuclear fuel cycle in the U.S. are about the same as those in the PV cycle; this contrasts European studies showing CO2 emissions from nuclear to be 10 lower than those from PV. |
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| Venue | Solar Program Review Meeting 2005 |
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| Source | Brookhaven National Laboratory |
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| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 10/2005 |
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| Post Date | 06/14/2005 |
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| Title | ENERGY AND LIFE CYCLE ASSESSMENT OF THIN FILM CDTE PHOTOVOLTAIC MODULES |
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| Link | (PDF 360 KB) Download Acrobat Reader. |
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| Author | M. Raugei |
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| Description | topic of this paper is the Life Cycle Assessment (LCA) of modern CdTe PV modules. The analysis was performed within the framework of the European research project PVACCEPT, and is based on actual
production data provided by the former project partner ANTEC Solar GmbH. This latter point makes the present LCA especially worthy of attention as a preliminary indication of the future environmental impact that the upscaling of CdTe module production may entail. The analysis is performed according to the recommendations of ISO norms 14040 and updates, and makes use of an original multi-criteria approach named SUMMA. The performance of the analysed CdTe system is also compared to other examples of advanced PV systems based on
different technologies (CIS and mc-Si), which were also part of the PVACCEPT project. Results clearly show an overall very promising picture for CdTe technology, which is found to be characterised by
favourable environmental impact indicators (e.g. 60g(abiotic matter)/kWh, 32 g(CO2-eq)/kWh and energy payback of 0.9 yrs. |
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| Venue | 20th EU PVSC Barcelona |
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| Source | University of Siena |
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| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 06/2005 |
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| Post Date | 06/13/2005 |
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| Title | IMPLICATIONS OF EUROPEAN ENVIRONMENTAL LEGISLATION FOR PHOTOVOLTAIC SYSTEMS |
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| Link | (PDF 434 KB) Download Acrobat Reader. |
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| Authors | M. J. De Wild-Scholten, K. Wambach, E. A. Alsema, A. Jager-Waldau |
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| Description | An overview is given of European environmental legislation which is effective now or proposed and which may have implications for the photovoltaic industry. The focus will be on legislation, which has been implemented already in national law, like the WEEE (waste electrical and electronic equipment)- and ROHS Reach (Registration, Evaluation, Authorisation and Restriction of Chemicals), F-gases (regulation on certain fluorinated greenhouse gases) and EuP (eco-design requirements for energy-using products). A change of the module design, with the research, development, implementation and certification necessary to be able to
produce photovoltaic systems that comply with such legislation, may be very time-consuming and expensive. Therefore a pro-active approach by the PV community is desirable. Environmental life cycle thinking and eco-design is becoming increasingly important as part of the European product and waste policy and will have its impact on the PV industry as well. Design-for-recycling must be encouraged to allow for an easy, cost-effective disassembly, with a high retrieval of for instance the precious crystalline silicon solar cells. A closed production cycle, i.e. guaranteed take back system, would probably prevent the commission as well as member states to impose legislative measures. |
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| Venue | 20th European PVSC Barcelona |
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| Sources | Deutsche Solar; Energy Research Centre of the Netherlands |
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| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 06/2005 |
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| Post Date | 06/29/2005 |
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| Title | NREL PAPERS FOR THE PVSC IN ORLANDO, 2005 |
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| Link | (MS Word 41 KB) |
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| Author | N/A |
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| Description | Links to about 20 papers in CIS, CdTe, a-Si, thin Si and reliability. |
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| Venue | |
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| Source | National Renewable Energy Laboratory |
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| Document Type | Conference Papers (Word document) |
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| Resource Date | 06/2005 |
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| Post Date | 06/14/2005 |
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| Title | EMPIRICAL TUNING METHODOLOGY FOR AS AND CL DOPING OF MOCVD GROWN CDTE |
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| Link | (PDF 192 KB) Download Acrobat Reader. |
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| Author | V. Barrioz |
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| Description | Photovoltaic solar cells based on CdTe absorbers are still showing comparitively high efficiencies, currently at 16.5%. However, these cells rely on CdCl2 treatments which are not fully understood and constrainflexibility over cell design. In this work, the effect of controlled arsenic and chlorine doping will be discussed as a potential alternative to CdCl2 treatments. The CdTe/CdS structures were grown by MOCVD onto commercial ITO/glass substrates. Numerous growth and post-growth parameters were varied such as; the II:VI precursor ratios, the substrate temperatures (Tsub) and the in situ post-growth annealing ambient gas (H2 or N2). A strategic statistical design of experiments, the Taguchi matrix method, was used, to establish the best combination of material parametersfor photovoltaic solar cell. High arsenic doping concentrations were needed to achieve a good photo-response in the test cells with a Jsc = 24.3 mA.cm-2, but the cell efficiency was limited by other parameters Voc = 0.55 V; FF = 40.9 %. The other main parameters increasing the cell efficiency were the in situ CdCl2 treatment and substrate temperatures of 315oC and 390oC during the growth of CdS and CdTe respectively. Any post-growth annealing at 500oC damaged considerably the photocurrent response. The method has been successful in showing rapid progress with a new approach, using 16 material and process parameters, in just 36 experiments, for achieving acceptable PV test cells. |
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| Venue | 20th EU PVSC Barcelona |
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| Source | University of Wales |
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| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 06/2005 |
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| Post Date | 05/09/2005 |
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| Title | CURRENT TRANSIENTS IN CDS/CDTE SOLAR CELLS |
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| Link | (PDF 194 KB) Download Acrobat Reader. |
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| Author | A. Fahrenbruch |
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| Description | Current transient responses to voltage and illumination steps are investigated to clarify the mechanisms involved in carrier transport in CdS/CdTe cells. For most cells, the response to a dark, forward-bias step after a long dark soak at zero bias is a current growth curve For one such
cell, the magnitude of the transient is ¡Ö 22% of the starting value with half of the growth occurring within ¡Ö 5 sec, the other half requiring 1000's of seconds. The effect is completely reversible and a mirror-image decay curve at zero bias after dark bias-on equilibration can be measured. Similarly, a complex of growth and decay curves are observed on application of illumination steps with constant bias. Similar transients have been observed by McMahon [1] and del Cueto et al. [2]. This is a survey of these effects in cells from three different fabricators. These transients, with varying magnitudes and directions, were seen in all the cells studied.
In general, the better the cell, the smaller the magnitudes of the transients. They range from changes by factors of 10 for pathological cells to subtle transients of 1-2% in excellent cells. Beside the important implications these transients have for accurate measurements of cell efficiency and stability, they provide clues about the carrier transport mechanisms.. One of the mechanisms proposed involves the occupation of deep donor traps with small hole cross sections, changing their recombination kinetics. The second hypothesis involves the modulation of the junction barrier profile by changing the charge on deep acceptors and donors by carrier trapping,
leading to a change in the effective junction barrier height. A third involves defect mutation such as that of [Cui] donors into [VCd]. |
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| Venue | Presented at the MRS Spring Meeting 3/28-4/1/2005, San Francisco REVISED 4/9/2005 |
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| Source | Colorado State University |
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| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 04/09/2005 |
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| Post Date | 04/05/2005 |
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| Title | PHYSICS OF CDTE PHOTOVOLTAICS: FROM FRONT TO BACK |
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| Link | (PDF 332 KB) Download Acrobat Reader. |
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| Authors | V. G. Karpov, et al. |
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| Description | We discuss physical mechanisms underlying the performance and stability of CdTe based thin-film PV. The processes in (i) photovoltaic junction, (ii) back contact, (iii) nonuniformities, (iv) grain boundaries, and (v) light-induced degradation are addressed including their interactions. The physics of thin film PV turns out to be quite different from that of crystalline PV. High surface-volume ratio and lack of crystallinity result in strong interfacial effects, lateral nonuniformities, and shunting-like and adhesion instabilities in thin film structures. This paper is aimed at presenting a ?big picture?; also, it suggests practical ways of improving thin-film PV. |
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| Venue | MRS Spring Meeting 2005, March 28 ? April 1, San Francisco, |
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| Source | University of Toledo |
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| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 03/28/2005 |
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| Post Date | 02/14/2005 |
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| Title | EARLY PERFORMANCE FOR THE ROOF-MOUNTED, 20-KW THIN FILM CDTE PV-ARRAY AT JASPER |
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| Link | (PDF 354 KB) Download Acrobat Reader. |
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| Author | J. H. Scofield |
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| Description | We report early performance for the grid-connected, 20-kW CdTe PV array installed on the roof of the Leslie Shao-ming Sun Field Station at the Jasper Ridge Biological Preserve. The array was installed in May 2002. Data are reported for 20-mos beginning April 2003. The array originally consisted of 275, BP Solar 80W thin-film CdTe modules arranged in 11-module strings. The monitoring system logged data from 9 sensors on 1-min intervals. Monitoring showed problems with maximum power tracking associated with module degradation, elevated module temperatures, and the finite voltage window of the 208VAC-3p inverter. The problems were addressed in May 2004 by re-wiring the array and reprogramming the inverter, resulting in a 20% increase in energy production. |
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| Venue | IEEE PVSC |
|---|
| Source | Oberlin College |
|---|
| Document Type | Conference Papers (Adobe Postscript file) |
|---|
| Resource Date | 01/2005 |
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|
| Post Date | 03/22/2005 |
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| Title | QUANTIFICATION OF LOSSES IN THIN-FILM CDS/CDTE SOLAR CELLS |
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| Link | (MS Word 3.5 MB) |
|---|
| Authors | S. Demetsu, J. R. Sites |
|---|
| Description | Quantification of solar cell losses can identify promising pathways for further cell improvements. This paper expands earlier work and applies it specifically to CdS/CdTe cells. For the analysis we have defined four cells: The Target cell is one that should be possible with current industrial processes. The Production cell is typical of today?s production. The Record cell has the highest efficiency (16.5%) reported to date. The Ideal cell has the highest theoretical performance for CdTe. The systematic technique of separating losses, referred to as third level metrics, breaks current, voltage, and fill-factor losses down into their individual loss mechanisms. The losses are expressed both as the deficiency in the specific parameter and as the impact on cell efficiency. The latter allows clear identification of the most significant losses. |
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| Venue | PVSC-31 IEEE |
|---|
| Source | Colorado State University |
|---|
| Document Type | Conference Papers (Word document) |
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| Resource Date | 01/2005 |
|---|
|
| Post Date | 03/22/2005 |
|---|
| Title | LBIC ANALYSIS OF THIN-FILM POLYCRYSTALLINE SOLAR CELLS |
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| Link | (MS Word 1.1 MB) |
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| Authors | T. J. Nagle, J. R. Sites |
|---|
| Description | Light-beam-induced-current (LBIC) measurements are providing a direct link between the spatial non-uniformities inherent in thin-film polycrystalline solar cells, such as CdTe and CIGS, and the overall performance of these cells. LBIC is uniquely equipped to produce quantitative maps of local quantum efficiency with relative ease. Spatial resolution of 1 ?m at 1-sun intensity, and return to the same area after other measurements, is routinely achieved. A wavelength range of 638 to 857 nm is available with diode lasers. The LBIC measurements demonstrate that several types of effects that alter cell performance can be traced to specific local-area features. Examples of such effects include defects related to edges, grids, or scribes, spatial variations in alloying, and local changes due to high-temperature stress. |
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| Venue | IEEE PVSC-31 |
|---|
| Source | Colorado State University |
|---|
| Document Type | Conference Papers (Word document) |
|---|
| Resource Date | 01/2005 |
|---|
|
| Post Date | 02/15/2005 |
|---|
| Title | EARLY PERFORMANCE FOR THE ROOF-MOUNTED, 20-KW THIN FILM CDTE PV-ARRAY AT JASPER RIDGE |
|---|
| Link | (PDF 364 KB) Download Acrobat Reader. |
|---|
| Authors | J. H. Scofield, et al. |
|---|
| Description | Here we report early performance for the grid-connected, 20-kW CdTe PV array installed on the roof of the Leslie Shao-ming Sun Field Station at the Jasper Ridge Biological Preserve. The array was installed in May 2002. Data are reported for 20-mos beginning April 2003. The array originally consisted of 275, BP Solar 80W thin-film CdTe modules arranged in 11-module strings. The monitoring system logged data from 9 sensors on 1-min intervals. Monitoring showed problems with maximum power tracking associated with module degradation, ele-vated module temperatures, and the finite voltage window of the 208VAC-3p inverter. The problems were addressed in May 2004 by re-wiring the array and reprogramming the inverter, resulting in a 20% increase in energy production. |
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| Venue | IEEE PVSC |
|---|
| Source | Oberlin College |
|---|
| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 01/2005 |
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|
| Post Date | 02/07/2005 |
|---|
| Title | THE ROLE OF POLYCRYSTALLIN THIN-FILM PV TECHNOLOGIES FOR ACHIEVING MID-TERM MARKET-COMPETITIVE PV MODULES |
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| Link | (MS Word 123 KB) |
|---|
| Authors | B. Von Roedern, K. Zweibel |
|---|
| Description | Using efficiency as the main parameter, projecting the cost competitiveness of thin films and x-Si. Current commercial status of CuInSe2 alloys (collectively, CIS) and CdTe-based photovoltaic (PV) modules, comparing the performance of commercial products with the results achieved for solar cell and prototype module champions. We provide an update for these PV cell and module technologies, and also compare CIS and CdTe performance levels to the results achieved by the crystalline Si PV industry. This comparison shows that CIS and CdTe module technology presently offers the best (and perhaps only) approach for significantly exceeding the cost/performance levels established by crystalline Si PV technologies. A semi-empirical methodology is used for comparing "champion" solar cell and prototype module data with performance achieved on manufacturing lines. Using a conservative assumption that thin-film technologies will eliminate the 40% of PV module costs arising from the Si wafer or ribbon, we estimate the future performance of all established PV module candidates, and conclude that, based on 2004 knowledge about each PV technology, CIS and CdTe should provide cost-competitive advantages over crystalline Si. |
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| Venue | IEEE PV Specialists Conference, 2004 |
|---|
| Source | National Renewable Energy Laboratory |
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| Document Type | Conference Papers (Word document) |
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| Resource Date | 01/2005 |
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|
| Post Date | 02/11/2005 |
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| Title | LIFE CYCLE ASSESSMENT OF PHOTOVOLTAICS: PERCEPTIONS, NEEDS, AND CHALLENGES |
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| Link | (PDF 222 KB) Download Acrobat Reader. |
|---|
| Authors | E. A. Alsema, M. J. De Wild-Scholten, V. Fthenakis |
|---|
| Description | High impact publications recently depicted PV technologies as having higher external environmental costs than those of nuclear energy and natural-gas-fueled power plants. These assessments are based on old data and unbalanced assumptions, and they illustrate the need for LCA data describing the continuously improving photovoltaic systems and the inclusion of social benefits in this comparison. |
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| Venue | IEEE Photovoltaic Specialistis Conference, Jan. 3-7, 2005, Orlando, FL |
|---|
| Sources | Brookhaven National Laboratory; Energy Research Centre of the Netherlands; Utrecht University |
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| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 01/2005 |
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|
| Post Date | 02/15/2005 |
|---|
| Title | ANALYTICAL RESULTS OF OUTPUT RESTRICTION DUE TO THE VOLTAGE INCREASING OF POWER DISTRIBUTION LINE IN GRID-CONNECTED CLUSTERED PV SYSTEMS |
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| Link | (PDF 2.4 MB) Download Acrobat Reader. |
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| Authors | Y. Ueda, et al. |
|---|
| Description | Output restriction to prevent over voltage of power distribution line is one of the concerns for grid-connected clustered PV systems. To investigate the behavior of clustered PV systems, "Demonstrative research on clustered PV systems" has being conducted from December, 2002 in Gunma, Japan. More than 200 residential PV systems are already installed in demonstrative research area. Operation point of array output is estimated using minutely averages of collected data. The method to quantify loss due to output restriction is developed in this study. |
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| Venue | IEEE PVSC |
|---|
| Source | Tokyo University |
|---|
| Document Type | Conference Papers (Adobe Postscript file) |
|---|
| Resource Date | 01/2005 |
|---|
|
| Post Date | 07/15/2005 |
|---|
| Title | QUANTIFICATION OF LOSSES IN THIN FILM CDS/CDTE CELLS |
|---|
| Link | (PDF 288 KB) Download Acrobat Reader. |
|---|
| Authors | S. Demetsu, J. R. Sites |
|---|
| Description | Quantification of solar cell losses can identify promising pathways for further cell improvements. This paper expands earlier work and applies it specifically to CdS/CdTe cells. For the analysis we have defined four cells: The Target cell is one that should be possible with current industrial processes. The Production cell is typical of today?s production. The Record cell has the highest efficiency (16.5%) reported to date. The Ideal cell has the highest theoretical performance for CdTe. The systematic technique of separating losses, referred to as third level metrics, breaks current, voltage, and fill-factor losses down into their individual loss mechanisms. The losses are expressed both as the deficiency in the specific parameter and as the impact on cell efficiency. The latter allows clear identification of the most significant losses. R- |
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| Venue | PVSC Orlando, FL 2005 |
|---|
| Source | Colorado State University |
|---|
| Document Type | Conference Papers (Adobe Postscript file) |
|---|
| Resource Date | 01/2005 |
|---|
|
| Post Date | 02/09/2005 |
|---|
| Title | TRANSPARENT CONTACT DEVELOPMENT FOR CDSE TOP CELLS IN HIGH EFFICIENCY TANDEM STRUCTURES |
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| Link | (MS Word 65 KB) |
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| Authors | P. Mahawala, et al. |
|---|
| Description | developing transparent contact/CdSe/transparent contact structures deposited on glass/SnO2:F. With these transparent structures we have demonstrated record Jsc's of 17.4 mA/cm2. SnO2 serves as the n contact, and the p contact is ZnSe:Cu. These structures have also exhibited sub band gap transmission of 80%. We have evaluated ZnO and CdS as alternative n contacts and ZnTe as an alternative p contact. Voc's of only 300 mV are being attained with ZnSe:Cu because its Fermi level seems to be near the middle of the band gap of CdSe in spite of favorable valence band alignment. However, using ZnTe:Cu as the p contact we have achieved Voc's up to 575 mV, a new high. |
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| Venue | IEEE |
|---|
| Source | University of South Florida, Tampa |
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| Document Type | Conference Papers (Word document) |
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| Resource Date | 11/2004 |
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|
| Post Date | 02/10/2005 |
|---|
| Title | CHARACTERISTICS OF CDTE FILMS OF DIFFERENT COMPOSITIONSFABRICATED BY CMBD |
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| Link | (MS Word 965 KB) |
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| Authors | T. M. Razykov, et al. |
|---|
| Description | CdTe films with near stoichiometric compositions and cadmium-rich compositions were fabricated by a novel low-cost chemical molecular beam deposition (CMBD) technique at atmospheric pressure under hydrogen or nitrogen gas flow. X-ray diffraction analysis and scanning electron microscopy studies show different grain growth by CMBD depending on the composition of samples. Those grown with cadmium rich compositions were of poor quality with large discontinuous island structures. On the other hand, samples grown with near stoichiometric compositions were polycrystalline with large grain size and uniform thickness. Additionally, films grown under nitrogen flow contained a cadmium tellurium oxide phase while those grown under hydrogen did not. |
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| Venue | 31st IEEE PVSC |
|---|
| Source | Uzbek Academy of Sciences |
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| Document Type | Conference Papers (Word document) |
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| Resource Date | 10/2004 |
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|
| Post Date | 02/09/2005 |
|---|
| Title | THE INFLUENCE OF VARIOUS FRONT CONTACT MATERIALS ON THE PERFORMANCE OF CDTE SOLAR CELLS |
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| Link | (MS Word 201 KB) |
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| Authors | R. Mamazza, et al. |
|---|
| Description | The use of a resistive, or buffer, layer in the front con-tact structure of CdTe solar cells has been known to improve solar cell performance, in particular when the CdS thickness is relatively small. This paper reviews the performance of CdTe solar cells fabricated on various front contact bi-layer combinations. Conductive (low-r) trans-parent oxides utilized for this work include SnO2:F, Cd2SnO4 and ITO; resistive (high-r) transparent oxides include SnO2, In2O3, and Zn2SnO4. All high-r layers were found to be effective within a range of processing condi-tions and process/device characteristics. Buffer layers of Zn-Sn-O appear to be the most promising high-? films for the fabrication of CdTe cells with small CdS thickness without compromising the VOC and FF. |
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| Venue | IEEE PVSC |
|---|
| Source | University of South Florida, Tampa |
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| Document Type | Conference Papers (Word document) |
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| Resource Date | 10/2004 |
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|
| Post Date | 02/09/2005 |
|---|
| Title | PHYSICAL MODES OF THIN-FILM PV DEGRADATION |
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| Link | (PDF 267 KB) Download Acrobat Reader. |
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| Authors | V. G. Karpov, et al. |
|---|
| Description | We discuss physical modes of degradation related to the small thickness and lack of crystallinity in thin-film PV. We discriminate between 1) uniform material degradation through defect generation, light-induced diffusion, and electro-migration; 2) nonuniform degradation through ohmic or non-ohmic shunts; 3) metal contact deterioration. The first can equally apply to bulk and thin-film PV. Two others are specific to thin-film PV. |
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| Venue | IEEE |
|---|
| Source | University of Toledo |
|---|
| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 10/2004 |
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|
| Post Date | 02/09/2005 |
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| Title | HIGH THROUGHPUT PROCESSING OF CDTE/CDS SOLAR CELLS |
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| Link | (MS Word 596 KB) |
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| Authors | B. E. McCandless, et al. |
|---|
| Description | Methods for achieving high throughput and materials yield in processing >13% efficient CdTe thin film solar cells are demonstrated, with emphasis on emiconductor deposition and post-deposition processing. Chemical surface deposition was used to deposit uniform 100 cm2 area CdS films 50 nm thick at 0.2 nm/sec, with >80% tilization of solvated Cd species. Vapor transport at 20 Torr was used to deposit dense CdTe films, 1-7 ?m thick, onto CdS-coated substrates with >50% utilization in an unbaffled system. Uniform films have been deposited with translation at up to 12 cm/min and static equivalent growth rate >80 ?m/min. Vapor CdCl2 post-deposition treatments yielded solar cells with AM1.5 conversion efficiency >13% for 6 mm thick CdTe and >8% for 1 mm thick CdTe. |
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| Venue | IEEE PVSC |
|---|
| Source | University of Toledo |
|---|
| Document Type | Conference Papers (Word document) |
|---|
| Resource Date | 10/2004 |
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|
| Post Date | 02/09/2005 |
|---|
| Title | RF SPUTTER ETCH AS A SURFACE CLEANING PROCESS FOR CDTE SOLAR CELLS |
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| Link | (MS Word 171 KB) |
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| Authors | V. Viswanathan, et al. |
|---|
| Description | The primary objective of this work is to investigate the potential of an alternative dry, vacuum-based process, as a surface modification step for CdTe prior to the application of the back contact electrode. RF-sputter etch has been used as an alternative surface cleaning process. The process was optimized for the type of etchant gas, pressure, time, and sputter power. Solar cells exhibited VOC's greater than 830 mV and FF's in the high 60's. This performance demonstrates the potential of this process for the development of an all-dry vacuum based CdTe technology. |
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| Venue | IEEE |
|---|
| Source | University of South Florida, Tampa |
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| Document Type | Conference Papers (Word document) |
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| Resource Date | 10/2004 |
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|
| Post Date | 02/08/2005 |
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| Title | INTRODUCTION OF CU IN CDS AND ITS EFFECT ON CDTE SOLAR CELLS |
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| Link | (MS Word 130 KB) |
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| Authors | K. Barri, et al. |
|---|
| Description | The use of copper during the fabrication of CdTe solar cells is a common feature for nearly all processing schemes developed for these devices. Copper is typically introduced in CdTe during the application of the back electrode, to enhance device performance by facilitating the formation of an ohmic back contact. However, Cu has also been associated with observed instability in CdTe. For this work, although Cu was utilized during the cell fabrication process, it was eliminated from the back contact formation step, and instead introduced in the CdS film prior to the deposition of the CdTe. The only fabrication step, where Cu was intentionally introduced, was subsequent to the CdS deposition. Both plain graphite and Sb2Te3/Mo were used as back contacts. Solar cell results suggested that ohmic contacts to CdTe can be attained with undoped graphite as the back electrode. For devices contacted with plain graphite VOC's and FF's in the range of 800-830 mV and 63-67% have been obtained. For Sb2Te3-contacted cells, the incorporation of Cu in CdS has lead to a significant increase in performance even though a back barrier was present in these cells. |
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| Venue | IEEE |
|---|
| Sources | National Renewable Energy Laboratory; University of South Florida, Tampa |
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| Document Type | Conference Papers (Word document) |
|---|
| Resource Date | 10/2004 |
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|
| Post Date | 02/08/2005 |
|---|
| Title | THERMAL ADMITTANCE SPECTROSCOPY STUDY: PRELIMINARY OBSERVATIONS OF A MEYER-NELDEL RELATIONSHIP IN CDTE DEVICES |
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| Link | (PDF 689 KB) Download Acrobat Reader. |
|---|
| Authors | K. L. Barth, R. A. Enzenroth, W. S. Sampath |
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| Description | CdTe analysis. |
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| Venue | IEEE |
|---|
| Source | Colorado School of Mines, Golden, CO |
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| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 10/2004 |
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|
| Post Date | 02/08/2005 |
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| Title | CONSISTENT PROCESSING AND LONG TERM STABILITY OF CDTE DEVICES |
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| Link | (PDF 1.4 MB) Download Acrobat Reader. |
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| Authors | K. L. Barth, R. A. Enzenroth, W. S. Sampath |
|---|
| Description | A technology for processing of thin film CdS/CdTe devices has been developed in our laboratory. This inline, continuous, pilot system enables unique processing steps and conditions not available with batch processing and allows the fabrication of a large number of devices. Results from the pilot scale system are applicable to systems processing larger areas. |
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| Venue | IEEE |
|---|
| Source | Colorado State University |
|---|
| Document Type | Conference Papers (Adobe Postscript file) |
|---|
| Resource Date | 10/2004 |
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|
| Post Date | 02/04/2005 |
|---|
| Title | STUDY OF POTENTIAL COST REDUCTIONS RESULTING FROM SUPER-LARGE-SCALE MANUFACTURING OF PV MODULES |
|---|
| Link | (MS Word 112 KB) |
|---|
| Authors | R. Arya, M. Keshner |
|---|
| Description | Short version of multi-GW production report |
|---|
| Venue | NREL Solar Review |
|---|
| Source | Hewlett Packard |
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| Document Type | Conference Papers (Word document) |
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| Resource Date | 10/2004 |
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|
| Post Date | 02/08/2005 |
|---|
| Title | THE IMPROVED INTRINSIC STABILITY OF CDTE POLYCRYSTALLINE THIN FILM DEVICES |
|---|
| Link | (PDF 137 KB) Download Acrobat Reader. |
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| Authors | D. Albin, et al. |
|---|
| Description | Parametric studies of CdS/CdTe device stability. |
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| Venue | DOE/NREL Solar Review 2004 |
|---|
| Source | National Renewable Energy Laboratory |
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| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 10/2004 |
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|
| Post Date | 02/11/2005 |
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| Title | EXPERIMENTAL INVESTIGATION OF EMISSIONS AND REDISTRIBUTION OF ELEMENTS IN CDTE PV MODULES DURING FIRES |
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| Link | (PDF 246 KB) Download Acrobat Reader. |
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| Authors | V. Fthenakis, et al. |
|---|
| Description | This study is based on glass-glass CdTe PV modules which are the only ones in the market. Pieces of commercial CdTe photovoltaic (PV) modules, sizes 3.8 cm by 30.5 cm, were heated to temperatures up to 1100ºC to simulate exposure to residential and commercial building fires. The temperature rate and duration in these experiments were defined according to standard UL and ASTM test protocols. Three different types of analysis were performed: measurements of sample weight loss as a function of temperature; analyses of Cd in the fire emissions; and analysis of Cd distribution in the molten glass, using Synchrotron x-ray fluorescence microprobe. It was found that a small amount of cadmium compounds (0.4 to 0.6% of the Cd content) was carried to the edges by the flow of EVA decomposition products. The pathway for this loss was through the perimeter of the sample before the two sheets of glass fused together. In actual size PV modules, the ratio of perimeter to area is 13.5 times smaller; thus the actual Cd loss during fires would be insignificant (<0.04% of the Cd content). |
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| Venue | European PV Solar Energy Conference, Paris, France, June 7-11, 2004; Paper 5BV.1.32 |
|---|
| Source | Brookhaven National Laboratory |
|---|
| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 06/2004 |
|---|
|
| Post Date | 02/09/2005 |
|---|
| Title | THE STATUS OF AND CHALLENGES IN CDTE THIN-FILM SOLAR-CELL TECHNOLOGY |
|---|
| Link | (PDF 160 KB) Download Acrobat Reader. |
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| Author | A. Compaan |
|---|
| Description | Polycrystalline CdTe thin- film solar cells have shown high potential for low cost, large-area module fabrication. But successful large-scale commercial production has been elusive. Fabrication of the basic n-CdS / p-CdTe heterojunction is possible by a wide variety of methods, including close-spaced sublimation, vapor-transport deposition, electrodeposition, chemical bath deposition, and magnetron sputtering. An overview of these methods is presented as well as the role of the postdeposition "activation" treatment using CdCl2. |
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| Venue | Spring 2004 MRS Symp. Amorphous and Nanocrystalline Silicon Science and Technology Proceedings to appear as MRS Symp. Proc. |
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| Source | University of Toledo |
|---|
| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 06/2004 |
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|
| Post Date | 02/09/2005 |
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| Title | CU K-EDGE X-RAY FINE STRUCTURE CHANGES IN CDTE WITH CDCL2 PROCESSING |
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| Link | (PDF 86 KB) Download Acrobat Reader. |
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| Authors | A. Compaan, X. Liu, et al. |
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| Description | MR-CAT beamline of the Advanced Photon Source at Argonne National Laboratory to study the fine structure in the Cu K-edge x-ray absorption in 3 mm thick polycrystalline films of CdTe on fused silica. 4 nm of evaporated Cu is diffused either with or without prior vapor CdCl2 treatments in dry air. Cu absorption is monitored through the Cu K a fluorescence using a 13 element Ge detector. The radial distribution junction inferred from the absorption fine structure indicates predominantly Cu2Te when Cu is diffused into the as deposited CdTe film but indicates a CuxO environment when Cu is diffused after the vapor CdCl2 treatment. |
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| Venue | European MRS |
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| Source | University of Toledo |
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| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 2004 |
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|
| Post Date | 02/07/2005 |
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| Title | TECHNOLOGY AND MARKET CHALLENGES TO MAINSTREAM THIN-FILM PHOTOVOLTAIC MODULES AND APPLICATIONS |
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| Link | (PDF 276 KB) Download Acrobat Reader. |
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| Author | R. Arya |
|---|
| Description | Technology and manufacturing advances over the past 25 years has led to widespread commercial use of thin film modules in many consumer applications. The three leading thin film solar module technologies are - amorphous silicon alloys (a-Si), copper indium diselenide alloys (CIGS), and cadmium telluride CdTe). These three technologies have demonstrated solar cells with efficiencies ~13% (a-Si), ~19% (CIGS), and ~16.5% (CdTe) respectively. Large area power modules are in various stages of initial production with these technologies and the module performance is in the 6%-11% range. Several manufacturing plants are in operation with plant capacities ranging from 3 MW to 30 MW. These plants are continuously increasing production with the present annual production of 1 MW to 5 MW. Technical challenges lie ahead in improving the module performance by reducing the gap between R&D cells and manufactured products so that they can successfully compete with crystalline silicon modules. Reliability of thin film modules in systems has been demonstrated with all three technologies with a fair degree of success. Several 1-480 kW grid-connected thin film module arrays are in deployment worldwide. Thin film modules are finding increasing acceptance for BIPV applications like roofs, facades, awnings etc. used in residential and commercial buildings. The cost of modules and market acceptance with new technologies still remains a major challenge to successful penetration of mainstream photovoltaic markets. |
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| Venue | |
|---|
| Source | N/A |
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| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 2004 |
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|
| Post Date | 02/09/2005 |
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| Title | STABILIZATION OF HIGH-EFFICIENCY CDTE PHOTOVOLTAIC MODULES IN CONTROLLED INDOOR LIGHT SOAKING |
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| Link | (PDF 330 KB) Download Acrobat Reader. |
|---|
| Authors | D. Cunningham, J. Pruett, J. A. del Cueto |
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| Description | The performance and stabilization of large-area, high-efficiency 9%, CdTe photovoltaic (PV) modules maintained under controlled light-soaking nominally at 800 Watts/m2 irradiance and 65°C module temperature are investigated. Degradation of module performance occurs predominantly in the first few hundred hours of exposure under these conditions; these symptoms included losses in fill factor (FF), open-circuit voltage (Voc), and short-circuit current (Isc), which amount to between 7% and 15% total loss in performance. Higher stabilized performance was achieved with lower copper content in the back contact. Transient effects in module V... |
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| Venue | |
|---|
| Sources | BP Solar; National Renewable Energy Laboratory |
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| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 2004 |
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|
| Post Date | 02/08/2005 |
|---|
| Title | CDTE BACK CONTACT: RESPONSE TO COPPER ADDITION AND OUT-DIFFUSION |
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| Link | (PDF 345 KB) Download Acrobat Reader. |
|---|
| Authors | C. Jenkins, et al. |
|---|
| Description | The back-contact barrier of CdTe solar cells plays an important role in cell operation, and it is substantially altered by both the amount of copper used in forming the contact and the movement of copper away from the contact during elevated temperature stress. It is shown that a simple model can explain the differences in current-voltage curves, cell uniformity, and capacitance as copper is added or moved out of the contact region, as well as the dependence of copper movement on electrical bias. |
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| Venue | draft |
|---|
| Source | Colorado State University |
|---|
| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 2004 |
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|
| Post Date | 02/04/2005 |
|---|
| Title | POLYCRYSTALLINE THIN-FILM PHOTOVOLTAIC TECHNOLOGIES: PROGRESS AND TECHNICAL ISSUES |
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| Link | (MS Word 1.5 MB) |
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| Author | H. S. Ullal |
|---|
| Description | Polycrystalline thin-film materials based on copper indium diselenide (CuInSe2, CIS) and cadmium telluride (CdTe) are promising thin-film solar cells for various power and specialty applications. Impressive results have been obtained in the past few years for both thin-film copper indium gallium diselenide (CIGS) solar cells and thin-film CdTe solar cells. NCPV/NREL scientists have achieved world-record, total-area efficiencies of 19.3% for a thin-film CIGS solar cell and 16.5% for thin-film CdTe solar cell. A number of technical R&D issues related to CIS and CdTe have been identified. Thin-film power module efficiencies up to 13.4% has been achieved thus far. Tremendous progress has been made in the technology development for module fabrication, and multi-megawatt manufacturing facilities are coming on line with expansion plans in the next few years. Several 40-480 kW polycrystalline thin-film, grid-connected PV arrays have been deployed worldwide. Hot and humid testing is also under way to validate the long-term reliability of these emerging thin-film power products. The U.S. thin-film production (amorphous silicon [a-Si], CIS, CdTe) is expected to exceed 50 MW by the end of 2005. |
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| Venue | PVSEC |
|---|
| Source | National Renewable Energy Laboratory |
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| Document Type | Conference Papers (Word document) |
|---|
| Resource Date | 2004 |
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|
| Post Date | 02/09/2005 |
|---|
| Title | NUMERICAL MODELING OF CIGS AND CDTE SOLAR CELLS: SETTING THE BASELINE |
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| Link | (MS Word 669 KB) |
|---|
| Authors | M. Gloeckler, et al. |
|---|
| Description | Numerical modeling of polycrystalline thin-film solar cells is an important strategy to test the viability of proposed physical explanations and to predict the effect of physical changes on cell performance. In general, this must be done with only partial knowledge of input parameters. Nevertheless, for consistent comparisons between laboratories, it is extremely useful to have a common starting point, or baseline. We will discuss guidelines that should be considered assigning input parameters for numerical modeling. Consequently specific baseline parameters for CIGS and CdTe are proposed. The modeling results for these baseline cases are presented and it is discussed how the baseline cases serve to describe some of the most important complications that are often found in experimental CIGS and CdTe solar cells. |
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| Venue | IEEE |
|---|
| Source | Colorado State University |
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| Document Type | Conference Papers (Word document) |
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| Resource Date | 2004 |
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|
| Post Date | 02/10/2005 |
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| Title | QUANTUM EFFICIENCY OF CDTE SOLAR CELLS IN FORWARD BIAS |
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| Link | (PDF 234 KB) Download Acrobat Reader. |
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| Authors | M. Gloeckler, J. R. Sites |
|---|
| Description | The quantum efficiency of a CdS/CdTe solar cell is measured under forward voltage, the measurement is likely affected by several factors including (1) the voltage dependence of the collection efficiency, (2) series resistance of the cell and instrumentation, (3) the electrical barrier of the back contact, (4) photoconductive effects in the CdS and CdTe, and (5) any secondary barrier in the primary junction. Each of these effects has a distinct signature, but without careful attention to these signatures, misinterpretation is possible and perhaps common. The approach here is to numerically simulate effect (1), and then progressively add effects (2), (3), (4), and (5). In each case, we show the characteristic signature of the apparent quantum efficiency when voltage is varied, we discuss the effect of bias light on the quantum efficiency measurement, we compare when possible with analytical modeling, and we show the impact of each effect on the cell's current-voltage curves, particularly the light/dark crossover. Although the presentation will be specific to CdTe cells, the principles should at least in part apply to other solar cells as well. |
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| Venue | Paris 2004 |
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| Source | Colorado State University |
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| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 2004 |
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|
| Post Date | 02/07/2005 |
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| Title | POLYCRYSTALLINE THIN-FILM PHOTOVOLTAIC TECHNOLOGIES: PROGRESS AND TECHNICAL ISSUES |
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| Link | (PDF 370 KB) Download Acrobat Reader. |
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| Author | H. S. Ullal |
|---|
| Description | Polycrystalline thin-film materials based on copper indium diselenide (CuInSe2, CIS) and cadmium telluride (CdTe) are promising thin-film solar cells for various power and specialty applications. Impressive results have been obtained in the past few years for both thin-film copper indium gallium diselenide (CIGS) solar cells and thin-film CdTe solar cells. NCPV/NREL scientists have achieved world-record, total-area efficiencies of 19.3% for a thin-film CIGS solar cell and 16.5% for thin-film CdTe solar cell. A number of technical R&D issues related to CIS and CdTe have been identified. Thin-film power module efficiencies up to 13.4% has been achieved thus far. Tremendous progress has been made in the technology development for module fabrication, and multi-megawatt manufacturing facilities are coming on line with expansion plans in the next few years. Several 40-480 kW polycrystalline thin-film, grid-connected PV arrays have been deployed worldwide. Hot and humid testing is also under way to validate the long-term reliability of these emerging thin-film power products. The U.S. thin-film production (amorphous silicon [a-Si], CIS, CdTe) is expected to exceed 50 MW by the end of 2005. |
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| Venue | PVSEC 19 |
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| Source | National Renewable Energy Laboratory |
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| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 2004 |
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|
| Post Date | 02/08/2005 |
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| Title | COPPER INCLUSION AND MIGRATION FROM THE BACK CONTACT IN CDTE SOLAR CELLS |
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| Link | (MS Word 791 KB) |
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| Authors | C. R. Corwine, et al. |
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| Description | Metallic back contacts to CdS/CdTe solar cells will in general form Schottky barriers. Better performance is achieved with the inclusion of Cu in the back contact. This study uses current-voltage, capacitance-voltage, and laser beam induced current measurements to analyze as-deposited CdS/CdTe solar cells prepared with varying back contact Cu amounts and to evaluate changes in cell performance following elevated-temperature stress. A simple model is proposed to explain both the observed differences in device behavior as copper is added or removed from the contact region, and how copper movement depends on electrical bias. |
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| Venue | Draft |
|---|
| Source | Colorado State University |
|---|
| Document Type | Conference Papers (Word document) |
|---|
| Resource Date | 2004 |
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|
| Post Date | 02/08/2005 |
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| Title | CONTINUOUS, IN-LINE PROCESSING OF CDS/CDTE DEVICES: PROGRESS TOWARDS CONSISTENT STABILITY |
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| Link | (PDF 98 KB) Download Acrobat Reader. |
|---|
| Authors | K. L. Barth, R. A. Enzenroth, W. S. Sampath |
|---|
| Description | A technology for continuous in-line processing of thin film CdS/CdTe devices has been developed in our laboratory. A CdTe PV device fabrication system has been operating for approximately 6 years and a full prototype manufacturing system for 16.5 x 16.5 inch substrates is under construction. Utilizing this technology, it has been demonstrated that at optimum process conditions good device stability (resistance to performance degradation) can be obtained. Two results pertaining to CdTe device stability are presented here: 1) The process conditions, particularly the CdCl2 treatment... |
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| Venue | EuroPV |
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| Source | Colorado State University |
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| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 2004 |
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|
| Post Date | 02/09/2005 |
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| Title | CONTINUOUS, IN-LINE PROCESSING OF CDS/CDTE DEVICES: PROGRESS TOWARDS CONSISTENT STABILITY |
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| Link | (PDF 98 KB) Download Acrobat Reader. |
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| Authors | K. L. Barth, R. A. Enzenroth, W. S. Sampath |
|---|
| Description | Two results pertaining to CdTe device stability are presented here: 1) The process conditions, particularly the CdCl 2 treatment, have a significant effect on device stability and 2) a saturation in the loss of efficiency over time in accelerated indoor stress has been observed for a large number of devices. CdTe, degradation, fabrication... |
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| Venue | EuroPV |
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| Source | Colorado State University |
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| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 2004 |
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|
| Post Date | 02/14/2005 |
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| Title | CIGS J-V DISTORTION IN THE ABSENCE OF BLUE PHOTONS |
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| Link | (MS Word 158 KB) |
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| Authors | A. O. Pudov, et al. |
|---|
| Description | Common buffer materials used with CuInGaSe2 (CIGS) absorbers produce conduction-band barriers that may significantly distort the current-voltage curves, especially when short-wavelength photons are excluded from the illumination spectrum. Earlier work documented this effect for CuInSe2 (CIS) absorbers (band gap near 1.0 eV) with CdS buffers. Higher band-gap (~1.15 eV) CIGS absorbers show little or no distortion with CdS buffer layers. However, wider band-gap (lower electron affinity) ZnS(O,OH) or InS(O,OH) buffers, prepared by chemical-bath deposition, clearly show the J-V distortion. The distortions have a turn-on time constant the order of a minute and turn-off time constant the order of a day, and they correlate with major variations in apparent quantum efficiency measured with varying intensity and spectral content of bias light. The results are consistent with a conduction-band spike barrier that increases with buffer band gap and is larger when the electron concentration in the buffer is small. |
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| Venue | EMRS |
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| Source | Colorado State University |
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| Document Type | Conference Papers (Word document) |
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| Resource Date | 2004 |
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|
| Post Date | 02/09/2005 |
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| Title | CU K-EDGE XAFS IN CDTE BEFORE AND AFTER TREATMENT WITH CDCL2 |
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| Link | (PDF 204 KB) Download Acrobat Reader. |
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| Authors | X. Liu, et al. |
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| Description | We have used the fine structure in the Cu K-edge x-ray absorption spectrum to help elucidate the lattice location of Cu in polycrystalline, thin-film CdTe solar cells. In particular, we have studied how the typical CdCl2 vapor treatment in dry air changes the local environment of the Cu in CdTe. We find the Cu absorption spectrum to be similar to that of Cu2Te in the asdeposited CdTe film but to convert to a spectrum similar to Cu2O environment after the vapor CdCl2 treatment. |
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| Venue | Materials Research Society Symposium Proceedings spring 2003, Symposium B "Compound Semiconductor Photovoltaics," paper B3.5 |
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| Source | University of Toledo |
|---|
| Document Type | Conference Papers (Adobe Postscript file) |
|---|
| Resource Date | 06/01/2003 |
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|
| Post Date | 02/09/2005 |
|---|
| Title | THE MESOSCALE PHYSICS OF LARGE-AREA PHOTOVOLTAICS |
|---|
| Link | (PDF 252 KB) Download Acrobat Reader. |
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| Authors | V. G. Karpov, et al. |
|---|
| Description | Recent findings make the physics of large-area thin-film devices a distinctive field of its own, considerably different from that of microelectronics. We show that (i) large-area thin-film photovoltaic (PV) devices are intrinsically nonuniform in the lateral directions, (ii) the nonuniformity spans over microscopically large dimensions, which can vary dramatically (from microns to meters) depending on light intensity and bias, and (iii) the nonuniformity significantly impacts the device performance and stability. Our understanding suggests the concept of interfacial layer that blocks the nonuniformity effects and can be applied photo-electrochemically. This concept is experimentally verified. |
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| Venue | 29th IEEE Osaka |
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| Source | University of Toledo |
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| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 05/16/2003 |
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|
| Post Date | 02/11/2005 |
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| Title | CDTE PV: REAL AND PERCEIVED EHS RISKS |
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| Link | (PDF 216 KB) Download Acrobat Reader. |
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| Authors | V. Fthenakis, K. Zweibel |
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| Description | As CdTe photovoltaics reached commercialization, questions were raised about potential cadmium emissions from CdTe PV modules. Some have attacked the CdTe PV technology as unavoidably polluting the environment, and made comparisons of hypothetical emissions from PV modules to cadmium emissions from coal-fired power plants. This paper gives an overview of the technical issues pertinent to these questions and further explores the potential of environmental, health, and safety (EHS) risks during production, use, and decommissioning of CdTe PV modules. The following issues are discussed: (a) the physical and toxicological properties of CdTe, (b) comparisons of Cd use in CdTe PV with its use in other technologies and products, and (c) the possibility of CdTe releases from PV modules. cells. |
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| Venue | NCPV and Solar Program Review Meeting 2003 NREL/CD-520-33586 Page 413 |
|---|
| Sources | Brookhaven National Laboratory; National Renewable Energy Laboratory |
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| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 2003 |
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|
| Post Date | 02/07/2005 |
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| Title | PRACTICAL DOPING PRINCIPLES |
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| Link | (PDF 270 KB) Download Acrobat Reader. |
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| Author | A. Zunger |
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| Description | Doping compound semiconductors. |
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| Venue | NREL DOE Solar Program Review Meeting 2003 |
|---|
| Source | National Renewable Energy Laboratory |
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| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 2003 |
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|
| Post Date | 02/02/2005 |
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| Title | COMPARISON OF ENERGY PRODUCTION AND PERFORMANCE FROM FLAT-PLATE PHOTOVOLTAIC MODULE TECHNOLOGIES DEPLOYED AT FIXED TILT |
|---|
| Link | (PDF 206 KB) Download Acrobat Reader. |
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| Author | J. A. del Cueto |
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| Description | energy rating by technology |
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| Venue | |
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| Source | National Renewable Energy Laboratory |
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| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 2003 |
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|
| Post Date | 02/07/2005 |
|---|
| Title | PROGRESS IN U.S. PHOTOVOLTAICS: LOOKING BACK 30 YEARS AND LOOKING AHEAD 20 |
|---|
| Link | (PDF 310 KB) Download Acrobat Reader. |
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| Author | T. Surek |
|---|
| Description | Technology and learning curve analysis of R&D. |
|---|
| Venue | Osaka IEEE |
|---|
| Source | National Renewable Energy Laboratory |
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| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 2003 |
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|
| Post Date | 02/09/2005 |
|---|
| Title | MANUFACTURING AND TECHNOLOGY DEVELOPMENT PROGRAMS AT FIRST SOLAR |
|---|
| Link | (PDF 334 KB) Download Acrobat Reader. |
|---|
| Authors | A. Abken, et al. |
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| Description | |
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| Venue | NCPV and Solar Program Review
NREL/CD-520-33586 |
|---|
| Source | First Solar, Toledo, OH |
|---|
| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 2003 |
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|
| Post Date | 02/09/2005 |
|---|
| Title | TEMPERATURE-DEPENDENT ELECTROLUMINESCENCE FROM CDTE/CDS SOLAR CELLS |
|---|
| Link | (PDF 87 KB) Download Acrobat Reader. |
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| Authors | K. J. Price, et al. |
|---|
| Description | Electroluminescence (EL) from polycrystalline CdTe/CdS solar cells was studied over the temperature range ? 30 C to 25 C. We are able to observe above-background EL at forward current densities as low as 3 mA/cm2, allowing us to explore the EL behavior at current-voltage regimes within the normal operating parameters of the device. The EL spectrum is very similar to the photoluminescence (PL) spectrum, and is independent of applied voltage. We show that the EL most likely originates from injected electron-hole recombination at the CdTe/CdS junction. The total EL intensity is found to vary as a power-law function of current... |
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| Venue | MRS 2003 |
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| Source | University of Toledo |
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| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 2003 |
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|
| Post Date | 02/10/2005 |
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| Title | PERTURBATION OF COPPER SUBSTITUTIONAL DEFECT CONCENTRATIONS IN CDS/CDTE HETEROJUNCTION SOLAR CELL DEVICES |
|---|
| Link | (PDF 565 KB) Download Acrobat Reader. |
|---|
| Authors | D. Albin, et al. |
|---|
| Description | The efficacy of implementing terrestrial-based photovoltaics is dictated by trade-offs in device performance, cost, and reliability. Presently, the highest efficiency polycrystalline CdS/CdTe superstrate solar cells utilize back contacts containing copper as an intentional dopant. Accelerated stress data correlates copper diffusion from this contact with performance degradation. Degradation at the device level exhibits two characteristic modes that are influenced by CdTe surface treatments prior to contacting. Rapid degradation associated with a rapidly decreasing open-circuit voltage can occur in cases where processing favors stoichiometric CdTe surfaces. Slower degradation associated with roll-over is typified by treatments favoring the presence of Te at the back contact. The chemical composition and extent of Te-rich contact interfaces is revealed by transmission electron microscopy. Deep-level transient spectroscopy of NP etched and non-etched devices show Te-rich conditions are necessary for the detection of deep-acceptor CuCd defect levels... |
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| Venue | Proceedings of Symposium F, 2002 Spring Meeting of the Materials Research Society San Francisco, CA April 1-5, 2002 |
|---|
| Source | National Renewable Energy Laboratory |
|---|
| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 05/2002 |
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|
| Post Date | 02/08/2005 |
|---|
| Title | EXTERNAL BIAS EFFECT ON JUNCTION PHOTOLUMINESCENCE IN CDS/CDTE SOLAR CELLS |
|---|
| Link | (PDF 421 KB) Download Acrobat Reader. |
|---|
| Authors | A. Compaan, V. G. Karpov, D. Shvydka |
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| Description | Study photoluminescence (PL) from the CdS/CdTe solar-cell junction region. We observed that applied external bias V does not change the spectral shape of the PL signal, but significantly affects the integral PL intensity I(V). It increases with moderate forward bias, tends to saturate when V is above the open-circuit voltage and is suppressed for reverse bias. |
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| Venue | IEEE |
|---|
| Source | University of Toledo |
|---|
| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 2002 |
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|
| Post Date | 02/09/2005 |
|---|
| Title | MICRONONUNIFORMITY EFFECTS IN THIN-FILM PHOTOVOLTAICS |
|---|
| Link | (PDF 350 KB) Download Acrobat Reader. |
|---|
| Authors | A. Compaan, V. G. Karpov, D. Shvydka |
|---|
| Description | We discuss effects of micrononuniformities on thin-film photovoltaics. The key factors are the device large area and the presence of potential barriers. We model the nonuniformity effects in the terms of random microdiodes connected in parallel through a resistive electrode. The microdiodes of low open circuit voltages affect macroscopically large regions. They strongly reduce the device performance and induce its nonuniform degradation in several different modes. We support our predictions by experiments. |
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| Venue | 2002 IEEE PVSC |
|---|
| Source | University of Toledo |
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| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 2002 |
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|
| Post Date | 02/07/2005 |
|---|
| Title | PV SOLAR ELECTRICITY: ONE AMONG THE NEW MILLENNIUM INDUSTRIES |
|---|
| Link | (PDF 6.0 MB) Download Acrobat Reader. |
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| Author | W. Hoffmann |
|---|
| Description | ABSTRACT: During recent years, solar electricity generation based on photovoltaics has developed into an industry at annual growth rates above 20%. Major market segments served by this industry comprise consumer applications, remote industrial systems, developing countries, and grid-connected systems. The potential in these markets supports sustained future growth, particularly for applications in developing countries and gridconnected systems in the industrial countries, where PV-generated electricity eventually will start to compete with peak grid power. Backed by price experience curves and a laboratory proven technology road map, a module turnover representing 100 billion
worlwide can be extrapolated. A sustainable energy contribution to the worldwide energy mix in subsequent decades is foreseen as a result of competitive PV solar electricity applications.
Keywords: PV Market Growth ? 1: Strategy ? 2: Cost Reduction ? 3 |
|---|
| Venue | 17th European Photovoltaic Solar Energy Conference, Munich, Germany, 22-26 October 2001 |
|---|
| Source | RWE Schott |
|---|
| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 10/2001 |
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|
| Post Date | 02/09/2005 |
|---|
| Title | EFFECT OF CDTE THICKNESS REDUCTION IN HIGH EFFICIENCY CDS/CDTE SOLAR CELLS |
|---|
| Link | (PDF 76 KB) Download Acrobat Reader. |
|---|
| Authors | A. Gupta, et al. |
|---|
| Description | High efficiency CdTe solar cells are typically grown with CdTe thicknesses from 3 to 15 mm, although the thickness required for 90% absorption of the incident irradiation at 800 nm is only ~1 mm. In this paper, we present the effect of CdTe thickness reduction on the performance of CdS/CdTe solar cells in which both the CdS and CdTe films were grown by sputtering. We produced a series of cells with different CdTe thickness (from 0.5 to 3.0 mm), and held the CdS thickness and back-contact-processing constant. The effect of CdTe thickness reduction on the diffusion of CdS into CdTe was studied using optical absorption and x-ray diffraction techniques. Only slight decreases occur in open-circuit voltage, short-circuit current, and fill factor with decrease in CdTe film thickness to 1.0 µm. Almost 10% efficient cells were obtained with 1 mm CdTe. Below 1 mm, all cell parameters decrease more rapidly, including the red quantum efficiency. |
|---|
| Venue | Mat. Res. Soc. Symp. Proc. Vol. 668 |
|---|
| Source | University of Toledo |
|---|
| Document Type | Conference Papers (Adobe Postscript file) |
|---|
| Resource Date | 2001 |
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|
| Post Date | 02/09/2005 |
|---|
| Title | PRECONTACT SURFACE CHEMISTRY EFFECTS ON CDS/CDTE SOLAR CELL PERFORMANCE AND STABILITY |
|---|
| Link | (PDF 76 KB) Download Acrobat Reader. |
|---|
| Authors | D. Albin, S. E. Asher, D. Levi, et al. |
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| Description | |
|---|
| Venue | 28th IEEE PVSC |
|---|
| Source | National Renewable Energy Laboratory |
|---|
| Document Type | Conference Papers (Adobe Postscript file) |
|---|
| Resource Date | 10/2000 |
|---|
|
| Post Date | 02/11/2005 |
|---|
| Title | HEALTH, SAFETY AND ENVIRONMENTAL ISSUES IN THIN FILM MANUFACTURING |
|---|
| Link | (PDF 50 KB) Download Acrobat Reader. |
|---|
| Authors | E. A. Alsema, et al. |
|---|
| Description | An investigation is made of Health, Safety and Environmental (HSE) aspects for the manufacturing, use and decommissioning of CdTe, CIS and a-Si modules. Issues regarding energy requirements, resource availability, emissions of toxic materials, occupational health and safety and module waste treatment are reviewed. Waste streams in thin film module manufacturing are analyzed in detail and treatment methods are discussed. Finally the technological options for thin film module recycling are investigated. It is concluded that there are no serious HSE bottlenecks for upscaling to production levels of 500 MWp/yr and that adequate methods are available for treatment of the manufacturing wastes. However, on the longer term issues regarding CdTe and CIS module waste treatment, In and Te resource availibility and module recycling need to adressed. Appropriate recycling methods for CdTe and CIS modules do not exist at present but the problem is being adressed by the PV industry. |
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| Venue | |
|---|
| Source | Utrecht University |
|---|
| Document Type | Conference Papers (Adobe Postscript file) |
|---|
| Resource Date | 2000 |
|---|
|
| Post Date | 02/09/2005 |
|---|
| Title | NONUNIFORM POWER GENERATION IN CDTE MODULES |
|---|
| Link | (PDF 516 KB) Download Acrobat Reader. |
|---|
| Authors | G. Dorer, R. Harju, V. G. Karpov |
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| Description | |
|---|
| Venue | IEEE PVSC |
|---|
| Source | First Solar, Toledo, OH |
|---|
| Document Type | Conference Papers (Adobe Postscript file) |
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| Resource Date | 2000 |
|---|
|
| Post Date | 02/09/2005 |
|---|
| Title | PROGRESS TOWARD CDTE CELL LIFE PREDICTION |
|---|
| Link | (PDF 1.9 MB) Download Acrobat Reader. |
|---|
| Authors | G. J. Jorgensen, T. J. McMahon |
|---|
| Description | Acclerated environmental testing. |
|---|
| Venue | NCPV PV Program Review 1999 |
|---|
| Source | National Renewable Energy Laboratory |
|---|
| Document Type | Conference Papers (Adobe Postscript file) |
|---|
| Resource Date | 1999 |
|---|
|
| Post Date | 02/11/2005 |
|---|
| Title | FIRST SOLAR'S CDTE MODULE MANUFACTURING EXPERIENCE; ENVIRONMENTAL, HEALTH AND SAFETY RESULTS |
|---|
| Link | (PDF 203 KB) Download Acrobat Reader. |
|---|
| Authors | J. R. Bohland, K. Smigielski |
|---|
| Description | Consistent with First Solar's proactive cadmium-containing material management practices such as CdTe PV module recycling, this paper reviews our activities and results in preventing environmental exposures and human health risks associated with cadmium materials processing during module manufacturing. Industrial hygiene data for manufacturing activities are presented and engineering controls are discussed. Medical monitoring results comparing recently hired to long-term employees and smokers is reported. Environmental releases to air, water and land have been quantified. |
|---|
| Venue | |
|---|
| Source | First Solar, Toledo, OH |
|---|
| Document Type | Conference Papers (Adobe Postscript file) |
|---|
| Resource Date | 1999 |
|---|
|
Back to Top Presentations
| Post Date | 05/18/2006 |
|---|
| Title | HIGH EFFICIENCY CDTE AND CIGS |
|---|
| Link | (PowerPoint 28.8 MB) |
|---|
| Author | R. Noufi |
|---|
| Description | Highlights and challenges |
|---|
| Venue | WCPEC4 oral |
|---|
| Source | National Renewable Energy Laboratory |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 05/2006 |
|---|
|
| Post Date | 06/13/2006 |
|---|
| Title | CDTE NATIONAL R&D TEAM MEETING 2006 |
|---|
| Link | (PDF 17.3 MB) Download Acrobat Reader. |
|---|
| Author | H. S. Ullal |
|---|
| Description | The presentations from the National R&D Team meeting and Voc Workshop; Large file! |
|---|
| Venue | National R&D Team meeting |
|---|
| Source | National Renewable Energy Laboratory |
|---|
| Document Type | Presentation (Adobe Postscript file) |
|---|
| Resource Date | 03/2006 |
|---|
|
| Post Date | 12/08/2005 |
|---|
| Title | ELECTRONIC STATES THAT CONTROL THE PERFORMANCE OF CDTE SOLAR CELLS |
|---|
| Link | (PowerPoint 1.1 MB) |
|---|
| Author | F. H. Seymour |
|---|
| Description | Admittance spectroscopy, defect correlation |
|---|
| Venue | NREL seminar Dec 7, 2005 |
|---|
| Source | Colorado School of Mines, Golden, CO |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 12/07/2005 |
|---|
|
| Post Date | 11/11/2005 |
|---|
| Title | THIN FILM PV PARTNERSHIP PROGRAM 2005 |
|---|
| Link | (PowerPoint 10.8 MB) |
|---|
| Author | K. Zweibel |
|---|
| Description | Overview of the purpose, strategies, and goals of the Thin Film Partnership Program, including updated module, BOS, and system cost projections for 2005 and 2020. |
|---|
| Venue | 2005 DOE Solar Review |
|---|
| Source | National Renewable Energy Laboratory |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 11/10/2005 |
|---|
|
| Post Date | 11/17/2005 |
|---|
| Title | THIN CDTE CELLS AND HIGH THROUGHPUT PROCESSING |
|---|
| Link | (PowerPoint 3.0 MB) |
|---|
| Author | B. E. McCandless |
|---|
| Description | under 1 micron CdTe; fast deposition |
|---|
| Venue | Solar Review 2005 |
|---|
| Source | University of Delaware |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 11/2005 |
|---|
|
| Post Date | 11/11/2005 |
|---|
| Title | ADVANCES IN CDTE R&D AT NREL |
|---|
| Link | (PowerPoint 1.5 MB) |
|---|
| Author | X. Wu |
|---|
| Description | Summary of efficiency, TCO, contact, and processing achievements in CdTe |
|---|
| Venue | 2005 DOE Solar Review |
|---|
| Source | National Renewable Energy Laboratory |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 11/2005 |
|---|
|
| Post Date | 11/11/2005 |
|---|
| Title | UNDERSTANDING THE PHYSICS OF CDS PV |
|---|
| Link | (PowerPoint 3.2 MB) |
|---|
| Author | V. G. Karpov |
|---|
| Description | piezo electric effect discussed |
|---|
| Venue | 2005 DOE Solar Review |
|---|
| Source | University of Toledo |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 11/2005 |
|---|
|
| Post Date | 11/17/2005 |
|---|
| Title | TECHNOLOGY IN SUPPORT OF THIN FILM CDTE PV MODULE MANUFACTURING |
|---|
| Link | (PowerPoint 9.6 MB) |
|---|
| Author | P. V. Meyers |
|---|
| Description | status of First Solar 2005 |
|---|
| Venue | DOE Solar Review 2005 |
|---|
| Source | First Solar, Toledo, OH |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 11/2005 |
|---|
|
| Post Date | 11/04/2005 |
|---|
| Title | PROGRESS IN CONTINUOUS IN-LINE CDS/CDTE DEPOSITION |
|---|
| Link | (PowerPoint 3.9 MB) |
|---|
| Author | W. S. Sampath |
|---|
| Description | Progress at CSU AVA Technologies in 2005 |
|---|
| Venue | DOE Solar Review Meeting |
|---|
| Sources | AVA Technologies; Colorado State University |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 11/2005 |
|---|
|
| Post Date | 11/18/2005 |
|---|
| Title | HOT AND HUMID THIN FILM MODULE TESTING IN FLORIDA |
|---|
| Link | (JPG 1.2 MB) |
|---|
| Author | N. G. Dhere |
|---|
| Description | various arrays are tested |
|---|
| Venue | DOE Solar Review 2005 poster |
|---|
| Source | FLorida Solar Energy Center |
|---|
| Document Type | Presentation (JPG image) |
|---|
| Resource Date | 11/2005 |
|---|
|
| Post Date | 11/23/2005 |
|---|
| Title | NANOSCALE-DESIGNED CERAMIC FILMS |
|---|
| Link | (PDF 1.9 MB) Download Acrobat Reader. |
|---|
| Author | S. Sambasivan |
|---|
| Description | thermal barriers, conformal alumina films, epitaxial oxide growth |
|---|
| Venue | Nanocommerce 2004, Chicago |
|---|
| Source | Applied thin films |
|---|
| Document Type | Presentation (Adobe Postscript file) |
|---|
| Resource Date | 10/2005 |
|---|
|
| Post Date | 09/02/2005 |
|---|
| Title | PV PAST THE TIPPING POINT |
|---|
| Link | (PowerPoint 31.8 MB) |
|---|
| Author | K. Zweibel |
|---|
| Description | Photovoltaics is growing rapidly, coming down in cost, and technical progress is substantial. We can be assured that PV costs will come down enough to provide electricity at an energy signifiant level. |
|---|
| Venue | Presntation at NREL to Norwegian StudyTour sponsored by CSM August 31, 2005 |
|---|
| Source | National Renewable Energy Laboratory |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 08/31/2005 |
|---|
|
| Post Date | 07/28/2005 |
|---|
| Title | 2002 TO 2005 THIN FILM PARTNERSHIP BUDGET TRENDS |
|---|
| Link | (PowerPoint 38 KB) |
|---|
| Author | K. Zweibel |
|---|
| Description | Budget in thin films for subcontracts is down 36% since 2002. |
|---|
| Venue | |
|---|
| Source | National Renewable Energy Laboratory |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 07/2005 |
|---|
|
| Post Date | 06/14/2005 |
|---|
| Title | INTEGRATED SYSTEMS FOR SOLAR RESEARCH: DAISY-SOL |
|---|
| Link | (PDF 477 KB) Download Acrobat Reader. |
|---|
| Authors | J. Fritsche, W. Jaegermann |
|---|
| Description | Setup CSS-CdTe CSS-CdS Chem. all in-situ solar cell manufacturing 2 dynamic CSS-chambers UHV-activation (in construction) backcontact formation (evaporation, sputtering) in-situ XPS/UPS-characterisation Rms [nm] |
|---|
| Venue | 20th EU PVSC, Barcelona, presentation |
|---|
| Source | Technische Universitat Darmstadt |
|---|
| Document Type | Presentation (Adobe Postscript file) |
|---|
| Resource Date | 06/2005 |
|---|
|
| Post Date | 06/14/2005 |
|---|
| Title | EMPIRICAL TUNING METHO FOR AS AND CL DOPING OF MOCVD CDTE |
|---|
| Link | (PDF 2.9 MB) Download Acrobat Reader. |
|---|
| Author | V. Barrioz |
|---|
| Description | doping studies of MOCVD CdTe |
|---|
| Venue | 20th EU PVSC, Barcelona, SuperGen |
|---|
| Source | University of Wales |
|---|
| Document Type | Presentation (Adobe Postscript file) |
|---|
| Resource Date | 06/2005 |
|---|
|
| Post Date | 05/10/2005 |
|---|
| Title | 13.9% EFFICIENT TRANSPARENT CDTE CELL WITH NIR TRNASMISSION OF ABOUT 50% |
|---|
| Link | (PowerPoint 1.8 MB) |
|---|
| Authors | X. Wu, et al. |
|---|
| Description | |
|---|
| Venue | CdTe National R&D Team |
|---|
| Source | National Renewable Energy Laboratory |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 05/06/2005 |
|---|
|
| Post Date | 05/09/2005 |
|---|
| Title | STABILITY OF CDS/CDTE WITH AG AND NI BACK CONTACTS |
|---|
| Link | (PowerPoint 2.4 MB) |
|---|
| Authors | D. Albin, A. Davies, S. Demetsu, T. J. McMahon, J. W. Pankow |
|---|
| Description | |
|---|
| Venue | CdTe R&D Team |
|---|
| Sources | Colorado State University; National Renewable Energy Laboratory |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 05/05/2005 |
|---|
|
| Post Date | 05/09/2005 |
|---|
| Title | INFLUENCE OF BAND PROFILES ON TRANSPORT AND RECOMBINATION IN CDTE |
|---|
| Link | (PowerPoint 2.4 MB) |
|---|
| Author | A. Fahrenbruch |
|---|
| Description | |
|---|
| Venue | CdTe R&D Team |
|---|
| Source | Colorado State University |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 05/05/2005 |
|---|
|
| Post Date | 05/09/2005 |
|---|
| Title | LUMINESCENCE STUDIES ON CU AND O DEFECTS IN CRYSTALLINE AND THIN CDTE |
|---|
| Link | (PDF 1.9 MB) Download Acrobat Reader. |
|---|
| Authors | C. R. Corwine, et al. |
|---|
| Description | |
|---|
| Venue | May 2005 CdTe National R&D Team meeting |
|---|
| Sources | Colorado State University; National Renewable Energy Laboratory |
|---|
| Document Type | Presentation (Adobe Postscript file) |
|---|
| Resource Date | 05/05/2005 |
|---|
|
| Post Date | 05/09/2005 |
|---|
| Title | MATERIALS CHEMISTRY AND ANALYSIS |
|---|
| Link | (PowerPoint 47 KB) |
|---|
| Author | B. E. McCandless |
|---|
| Description | |
|---|
| Venue | CdTe R&D Team |
|---|
| Source | University of Delaware |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 05/05/2005 |
|---|
|
| Post Date | 05/09/2005 |
|---|
| Title | CDTE STABILITY SUBTEAM |
|---|
| Link | (PowerPoint 911 KB) |
|---|
| Author | D. Albin |
|---|
| Description | |
|---|
| Venue | CdTe R&D Team |
|---|
| Source | National Renewable Energy Laboratory |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 05/05/2005 |
|---|
|
| Post Date | 05/09/2005 |
|---|
| Title | COPPER AND BUFFER LAYER EFFECTS |
|---|
| Link | (PowerPoint 13.5 MB) |
|---|
| Authors | D. Albin, S. Demetsu |
|---|
| Description | |
|---|
| Venue | CdTe R&D Team |
|---|
| Sources | Colorado State University; National Renewable Energy Laboratory |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 05/05/2005 |
|---|
|
| Post Date | 05/09/2005 |
|---|
| Title | PL STUDIES OF CDTE CRYSTALS ION-IMPLANTED WITH CL, CU, OR P |
|---|
| Link | (PowerPoint 285 KB) |
|---|
| Authors | L. Gorrell, S. Liu |
|---|
| Description | |
|---|
| Venue | CdTe R&D Team |
|---|
| Source | University of Toledo |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 05/05/2005 |
|---|
|
| Post Date | 05/09/2005 |
|---|
| Title | HOW THIN FILM PV CAN BE DIFFERENT |
|---|
| Link | (PowerPoint 122 KB) |
|---|
| Author | V. G. Karpov |
|---|
| Description | different device models of CdTe cells, weak diodes, MIS, degradation |
|---|
| Venue | CdTe R&D Team |
|---|
| Source | University of Toledo |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 05/05/2005 |
|---|
|
| Post Date | 05/09/2005 |
|---|
| Title | NONLINEAR SHUNTING IN CDTE |
|---|
| Link | (PowerPoint 201 KB) |
|---|
| Authors | V. G. Karpov, D. Shvydka |
|---|
| Description | |
|---|
| Venue | CdTe R&D Team |
|---|
| Source | University of Toledo |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 05/05/2005 |
|---|
|
| Post Date | 05/09/2005 |
|---|
| Title | REAL-TIME, IN-SITU ELLIPSOMETRY OF CDTE FILM GROWTH AND SOLAR CELL ETCH-BACK |
|---|
| Link | (PowerPoint 5.2 MB) |
|---|
| Author | R. W. Collins |
|---|
| Description | |
|---|
| Venue | CdTe National R&D Team meeting |
|---|
| Source | University of Toledo |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 05/05/2005 |
|---|
|
| Post Date | 05/09/2005 |
|---|
| Title | PIEZO EFFECT IN CDS/CDTE SOLAR CELLS |
|---|
| Link | (PowerPoint 1.4 MB) |
|---|
| Authors | D. Shvydka, et al. |
|---|
| Description | |
|---|
| Venue | CdTe R&D Team |
|---|
| Source | University of Toledo |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 05/05/2005 |
|---|
|
| Post Date | 05/09/2005 |
|---|
| Title | SENSITIVITY OF THIN FILM CDTE DEVICE OPERATION TO PROCESSING CHEMISTRY |
|---|
| Link | (PowerPoint 1.5 MB) |
|---|
| Author | B. E. McCandless |
|---|
| Description | |
|---|
| Venue | CdTe R&D Team |
|---|
| Source | University of Delaware |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 05/05/2005 |
|---|
|
| Post Date | 05/11/2005 |
|---|
| Title | SOLAR FIELDS, LLC |
|---|
| Link | (PowerPoint 1.2 MB) |
|---|
| Author | K. Kormanyos |
|---|
| Description | Introduction to status and plans |
|---|
| Venue | National CdTe R&D Meeting |
|---|
| Source | Solar Fields |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 05/05/2005 |
|---|
|
| Post Date | 05/09/2005 |
|---|
| Title | STABILITY STUDIES WITH CSU AND UT CDTE CELLS |
|---|
| Link | (PowerPoint 4.4 MB) |
|---|
| Author | L. Olsen |
|---|
| Description | |
|---|
| Venue | CdTe R&D Team |
|---|
| Source | Pacific Northwest National Lab (PNNL) |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 05/05/2005 |
|---|
|
| Post Date | 05/09/2005 |
|---|
| Title | CHOOSING DEFECT PROPERTIES FOR DEVICE MODELING |
|---|
| Link | (PowerPoint 1.1 MB) |
|---|
| Author | A. Fahrenbruch |
|---|
| Description | |
|---|
| Venue | CdTe R&D Team |
|---|
| Source | Colorado State University |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 05/05/2005 |
|---|
|
| Post Date | 05/09/2005 |
|---|
| Title | STEADY STATE PHOTOCAPACITANCE OF CDTE CELLS |
|---|
| Link | (PowerPoint 561 KB) |
|---|
| Author | R. A. Enzenroth |
|---|
| Description | |
|---|
| Venue | CdTe R&D Team |
|---|
| Source | Colorado State University |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 05/05/2005 |
|---|
|
| Post Date | 05/09/2005 |
|---|
| Title | BIFACIAL CDS/CDTE/ZNTE DEVICE CHARACTERIZATION |
|---|
| Link | (PowerPoint 645 KB) |
|---|
| Authors | D. Desai, S. S. Hegedus |
|---|
| Description | |
|---|
| Venue | CdTe National R&D Team |
|---|
| Source | University of Delaware |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 05/05/2005 |
|---|
|
| Post Date | 05/09/2005 |
|---|
| Title | CU AND CDCL2 INFLUENCE ON DEEP DEFECTS IN CDTE CELLS |
|---|
| Link | (PowerPoint 285 KB) |
|---|
| Authors | D. Albin, V. Kaydanov, T. Ohno, F. H. Seymour |
|---|
| Description | |
|---|
| Venue | CdTe R&D Team |
|---|
| Sources | Colorado School of Mines, Golden, CO; National Renewable Energy Laboratory |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 05/05/2005 |
|---|
|
| Post Date | 05/09/2005 |
|---|
| Title | X-RAY FINE STRUCTURE OF CU IN SPUTTERED CDTE (OR WHERE DOES THE CU GO?) |
|---|
| Link | (PowerPoint 1.1 MB) |
|---|
| Authors | S. Liu, et al. |
|---|
| Description | |
|---|
| Venue | CdTe R&D Team |
|---|
| Source | University of Toledo |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 05/05/2005 |
|---|
|
| Post Date | 05/09/2005 |
|---|
| Title | CONDUCTIVE ATOMIC FORCE MICROSCOPY APPLIED TO CDTE/CDS CELLS |
|---|
| Link | (PowerPoint 3.2 MB) |
|---|
| Authors | H. Moutinho, et al. |
|---|
| Description | |
|---|
| Venue | CdTe R&D Team |
|---|
| Source | National Renewable Energy Laboratory |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 05/05/2005 |
|---|
|
| Post Date | 05/09/2005 |
|---|
| Title | ADVANCES IN CONTINUOUS IN-LINE PROCESSING OF CDTE PV DEVICES |
|---|
| Link | (PowerPoint 1.7 MB) |
|---|
| Authors | K. L. Barth, R. A. Enzenroth, W. S. Sampath |
|---|
| Description | |
|---|
| Venue | CdTe R&D Team |
|---|
| Source | Colorado State University |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 05/05/2005 |
|---|
|
| Post Date | 05/09/2005 |
|---|
| Title | EFFECT OF APPLIED BIAS DURING STRESS: OLD AND NEW RESULTS FOCUSING ON CU CONTACT |
|---|
| Link | (PowerPoint 706 KB) |
|---|
| Authors | S. S. Hegedus, et al. |
|---|
| Description | |
|---|
| Venue | CdTe R&D Team |
|---|
| Source | University of Delaware |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 05/05/2005 |
|---|
|
| Post Date | 05/09/2005 |
|---|
| Title | CDS:CU AND BUFFER LAYERS |
|---|
| Link | (PowerPoint 496 KB) |
|---|
| Authors | C. S. Ferekides, et al. |
|---|
| Description | |
|---|
| Venue | CdTe R&D Team |
|---|
| Source | University of South Florida, Tampa |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 05/05/2005 |
|---|
|
| Post Date | 05/09/2005 |
|---|
| Title | CDS/CDTE THICKNESS AND O2 EFFECTS ON STABILITY |
|---|
| Link | (PowerPoint 1.5 MB) |
|---|
| Authors | D. Albin, S. Demetsu, T. J. McMahon |
|---|
| Description | |
|---|
| Venue | CdTe R&D Team |
|---|
| Sources | Colorado State University; National Renewable Energy Laboratory |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 05/05/2005 |
|---|
|
| Post Date | 05/09/2005 |
|---|
| Title | ESTIMATION OF ACCELERATION FACTORS BY COMPARISON OF PERFORMANCE DURING ACCELERATED STRESS AND IN OUTDOOR CONDITIONS |
|---|
| Link | (PowerPoint 188 KB) |
|---|
| Author | R. A. Enzenroth |
|---|
| Description | |
|---|
| Venue | CdTe R&D Team |
|---|
| Source | Colorado State University |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 05/05/2005 |
|---|
|
| Post Date | 05/09/2005 |
|---|
| Title | PROGRESS AT AVA TECHNOLOGIES |
|---|
| Link | (PowerPoint 2.0 MB) |
|---|
| Authors | K. L. Barth, et al. |
|---|
| Description | |
|---|
| Venue | CdTe R&D Team |
|---|
| Source | AVA Technologies |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 05/05/2005 |
|---|
|
| Post Date | 03/17/2005 |
|---|
| Title | ALTERNATIVE JUNCTION SUBTEAM |
|---|
| Link | (PowerPoint 851 KB) |
|---|
| Author | J. R. Sites |
|---|
| Description | comparing different junction partners and absorber band gaps |
|---|
| Venue | CIS National R&D Team Meeting March 2005 NREL |
|---|
| Source | Colorado State University |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 03/08/2005 |
|---|
|
| Post Date | 02/09/2005 |
|---|
| Title | NREL CDTE RESEARCH |
|---|
| Link | (PowerPoint 6.3 MB) |
|---|
| Authors | T. Gessert, et al. |
|---|
| Description | |
|---|
| Venue | DOE Solar Review |
|---|
| Source | National Renewable Energy Laboratory |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 10/28/2004 |
|---|
|
| Post Date | 02/09/2005 |
|---|
| Title | HIGH THROUGHPUT PROCESSING OF STABLE CDTE/CDS SOLAR CELLS |
|---|
| Link | (PowerPoint 2.0 MB) |
|---|
| Authors | B. E. McCandless, et al. |
|---|
| Description | |
|---|
| Venue | DOE Solar Review 2004 |
|---|
| Source | University of Delaware |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 10/26/2004 |
|---|
|
| Post Date | 02/10/2005 |
|---|
| Title | TOWARD A TANDEM CELL WITH ALL II-VI SEMICONDUCTORS BY MAGNETRON SPUTTERING |
|---|
| Link | (PDF 1.2 MB) Download Acrobat Reader. |
|---|
| Authors | A. Compaan, et al. |
|---|
| Description | CdTe/HgCdTe |
|---|
| Venue | DOE Solar Review |
|---|
| Source | University of Toledo |
|---|
| Document Type | Presentation (Adobe Postscript file) |
|---|
| Resource Date | 10/25/2004 |
|---|
|
| Post Date | 02/09/2005 |
|---|
| Title | LARGE AREA THIN FILM DEVICES: NONUNIFORMITIES, INTERFACIAL LAYESR, REACG-THROUGH EFFECTS |
|---|
| Link | (PowerPoint 884 KB) |
|---|
| Author | V. G. Karpov |
|---|
| Description | |
|---|
| Venue | DOE Solar Review |
|---|
| Source | University of Toledo |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 10/2004 |
|---|
|
| Post Date | 02/07/2005 |
|---|
| Title | THIN FILMS AND THE SYSTEM DRIVEN APPROACH |
|---|
| Link | (PowerPoint 1.0 MB) |
|---|
| Author | K. Zweibel |
|---|
| Description | Cost analysis of thin films for semiconductor, encapusulation, layer thickness, and efficiency. |
|---|
| Venue | DOE and NREL Solar Review Meeting 2004 |
|---|
| Source | National Renewable Energy Laboratory |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 10/2004 |
|---|
|
| Post Date | 02/07/2005 |
|---|
| Title | 2ND GENERATION THIN FILMS |
|---|
| Link | (PowerPoint 8.9 MB) |
|---|
| Author | K. Zweibel |
|---|
| Description | Potential of CIS, CdTe, and a-Si thin films. |
|---|
| Venue | Rice University Solar Energy Workshop |
|---|
| Source | National Renewable Energy Laboratory |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 09/2004 |
|---|
|
| Post Date | 04/22/2005 |
|---|
| Title | EFFECTS OF MOISTURE INGRESS ON PV MODULES |
|---|
| Link | (PDF 528 KB) Download Acrobat Reader. |
|---|
| Author | M. Kempe |
|---|
| Description | Measuring the rate water vapor moves through EVA from the edge and the back |
|---|
| Venue | Thin Film Module Reliability National Team Meeting |
|---|
| Source | National Renewable Energy Laboratory |
|---|
| Document Type | Presentation (Adobe Postscript file) |
|---|
| Resource Date | 06/2004 |
|---|
|
| Post Date | 04/22/2005 |
|---|
| Title | LEAKAGE CURRENTS AND HIGH-VOLTAGE THIN FILM MODULES |
|---|
| Link | (PDF 1.1 MB) Download Acrobat Reader. |
|---|
| Author | N. G. Dhere |
|---|
| Description | FSEC testing of outdoor thin film arrays |
|---|
| Venue | Thin Film Module Reliability Team Meeting |
|---|
| Source | FLorida Solar Energy Center |
|---|
| Document Type | Presentation (Adobe Postscript file) |
|---|
| Resource Date | 06/2004 |
|---|
|
| Post Date | 04/22/2005 |
|---|
| Title | ADHESION TESTS OF CANDIDATE BACKSHEET AND ENCAPSULANTS |
|---|
| Link | (PDF 425 KB) Download Acrobat Reader. |
|---|
| Authors | G. J. Jorgensen, J. A. del Cueto, et al. |
|---|
| Description | Pull tests of various candidate replacements for EVA |
|---|
| Venue | Thin film module reliability national team meeting |
|---|
| Source | National Renewable Energy Laboratory |
|---|
| Document Type | Presentation (Adobe Postscript file) |
|---|
| Resource Date | 06/2004 |
|---|
|
| Post Date | 04/22/2005 |
|---|
| Title | MOISTURE INGRESS PROTECTION BY COMBINED BACKSHEET AND ENCAPSULANT CONSTRUCTIONS |
|---|
| Link | (PDF 1.7 MB) Download Acrobat Reader. |
|---|
| Authors | G. J. Jorgensen, M. Kempe, C. Kennedy, K. Terwilliger |
|---|
| Description | WVTR, PET, EVA, BRP, TruSeal |
|---|
| Venue | Thin Film Module Reliability National Team Meeting |
|---|
| Source | National Renewable Energy Laboratory |
|---|
| Document Type | Presentation (Adobe Postscript file) |
|---|
| Resource Date | 06/2004 |
|---|
|
| Post Date | 04/22/2005 |
|---|
| Title | PAST AND PREDICTED THIN FILM MODULE PRODUCTION IN THE US BY TECHNOLOGY |
|---|
| Link | (PowerPoint 45 KB) |
|---|
| Author | K. Zweibel |
|---|
| Description | Annual MWp/yr 2000-2011 by technology |
|---|
| Venue | |
|---|
| Source | National Renewable Energy Laboratory |
|---|
| Document Type | Presentation (Powerpoint presentation) |
|---|
| Resource Date | 04/22/2004 |
|---|
|
| Post Date | 02/11/2005 |
|---|
| Title | PV MODULE RECYCLING IN THE US |
|---|
| Link | (PDF 600 KB) Download Acrobat Reader. |
|---|
| Authors | V. Fthenakis, K. Zweibel |
|---|
| Description | Recycling today and tomorrow |
|---|
| Venue | EIA Workshop |
|---|
| Source | N/A |
|---|
| Document Type | Presentation (Adobe Postscript file) |
|---|
| Resource Date | 03/2004 |
|---|
|
| Post Date | 02/11/2005 |
|---|
| Title | PV MODULE RECYCLING IN THE US |
|---|
| Link | (PowerPoint 3.8 MB) |
|---|
| Authors | V. Fthenakis, K. Zweibel |
|---|
| Description | Recycling today and tomorrow. |
|---|
| Venue | EU Workshop "Waste Challenge" |
|---|
| Sources | Brookhaven National Laboratory; National Renewable Energy Laboratory |
|---|
| Document Type | Presentation (Powerpoint presentation) |
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| Resource Date | 03/2004 |
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|
| Post Date | 02/07/2005 |
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| Title | PV AS A MAJOR SOURCE OF GLOBAL ELECTRICITY |
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| Link | (PowerPoint 13.2 MB) |
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| Author | K. Zweibel |
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| Description | Projected improvements needs to make PV a major source of electricity. |
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| Venue | University of Toledo |
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| Source | National Renewable Energy Laboratory |
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| Document Type | Presentation (Powerpoint presentation) |
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| Resource Date | 02/24/2004 |
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|
| Post Date | 02/17/2005 |
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| Title | A COMPARISON OF THIN FILMS AND X-SI IN THE US MARKET, HISTORICAL AND PROJECTED |
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| Link | (MS Word 31 KB) |
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| Author | K. Zweibel |
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| Description | Thin films are gaining ground on x-Si and are projected to overtake it in the US about 2010-2011. |
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| Venue | Thin Film Partnership and Paul Maycock's PV News February 2005 |
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| Source | PV News |
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| Document Type | Presentation (Word document) |
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| Resource Date | 02/17/2004 |
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|
| Post Date | 02/11/2005 |
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| Title | TRAPPING ALMOST ALL CD IN GLASS ENCAPSULATION IN THE EVENT OF A RESIDENTIAL FIRE: DETAILED EXPERIMENTAL ANALYSIS |
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| Link | (PowerPoint 45.7 MB) |
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| Author | V. Fthenakis |
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| Description | |
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| Venue | |
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| Source | Brookhaven National Laboratory |
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| Document Type | Presentation (Powerpoint presentation) |
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| Resource Date | 2004 |
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|
| Post Date | 02/15/2005 |
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| Title | THE INTRINSIC STABILITY OF POLYCRYSTALLINE THIN FILM SOLAR CELLS |
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| Link | (PowerPoint 3.0 MB) |
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| Authors | D. Albin, T. Berniard, S. Demetsu, T. J. McMahon, R. Noufi |
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| Description | Indoor, accelerated tests of thin film CIS and CdTe |
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| Venue | |
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| Sources | Colorado State University; National Renewable Energy Laboratory |
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| Document Type | Presentation (Powerpoint presentation) |
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| Resource Date | 2004 |
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|
| Post Date | 02/09/2005 |
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| Title | SUMMARY OF EXPERIMENTS WITH TE THICKNESS VARIATION |
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| Link | (PDF 67 KB) Download Acrobat Reader. |
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| Authors | K. D. Dobson, B. E. McCandless |
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| Description | summary of experiments we have performed to examine the effect of Te thickness on cell stability. At the end we comment on how these results are related to humidity effects during processing and stress. |
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| Venue | |
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| Source | University of Delaware |
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| Document Type | Presentation (Adobe Postscript file) |
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| Resource Date | 09/05/2003 |
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|
| Post Date | 02/09/2005 |
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| Title | MAGNETRON SPUTTERING FOR LOW TEMPERATURE DEPOSITION OF CDTE PV |
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| Link | (PowerPoint 1.0 MB) |
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| Author | A. Compaan |
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| Description | |
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| Venue | MRS Spring 2003 |
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| Source | University of Toledo |
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| Document Type | Presentation (Powerpoint presentation) |
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| Resource Date | 05/2003 |
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|
| Post Date | 02/09/2005 |
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| Title | THE DYNAMICS OF CADMIUM TELLURIDE ETCHING |
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| Link | (PDF 192 KB) Download Acrobat Reader. |
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| Authors | K. D. Dobson, et al. |
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| Description | CdTe etching was investigated using variable angle spectroscopic ellipsometry and glancing angle x-ray diffraction. Treatment with HNO3:H3PO4 (NP) based etches was shown to form amorphous-Te surface films which spontaneously crystallize following etching. Br2/methanol (BM) etching forms very thin amorphous-Te films. NP-etched surfaces are stable in ambient air... |
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| Venue | CdTe Team Meeting |
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| Source | University of Delaware |
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| Document Type | Presentation (Adobe Postscript file) |
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| Resource Date | 2003 |
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|
| Post Date | 02/07/2005 |
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| Title | PROGRESS IN US PV |
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| Link | (PowerPoint 1.5 MB) |
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| Author | T. Surek |
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| Description | 50 years of progress in PV. |
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| Venue | Osaka IEEE conference |
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| Source | National Renewable Energy Laboratory |
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| Document Type | Presentation (Powerpoint presentation) |
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| Resource Date | 2003 |
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|
| Post Date | 02/09/2005 |
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| Title | WHEN, WHY AND WHERE ARE CDTE/CDS SOLAR CELLS STABLE? |
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| Link | (MS Word 960 KB) |
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| Authors | K. D. Dobson, I. Visoly-Fisher, et al. |
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| Description | The role of Cu in CdTe/CdS solar cell instability remains the subject of much debate. The investigation of a range of 'Cu'-contacted CdTe/CdS cells, which had received various thermal stress treatments, is described. Cells that were stressed in air exhibit strong current-voltage (I-V) rollover and junction degradation. No such degradation was observed for 'Cu'-contacted cells that had been stressed in dry-N2 atmosphere. Cu is found to diffuse rapidly through the cell structure during back contact annealing and to accumulate in the CdS layer. With stress, significant levels of Cu dope the grain bulk, producing (with Cl) high resistance, photo-conducting CdS. This behavior is independent of stress atmosphere and is, therefore, unlikely to (initially) be a dominating mechanism for cell degradation. Our results suggest simple air oxidation of the back contact interface to be a likely origin of I-V rollover in CdTe/CdS cells. |
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| Venue | CdTe Team Meeting |
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| Source | Weizmann Institute |
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| Document Type | Presentation (Word document) |
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| Resource Date | 2003 |
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|
Back to Top Annual/Final Reports
| Post Date | 07/09/2008 |
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| Title | PROCESSING MATERIALS, DEVICES AND DIAGNOSTICS FOR THIN FILM PHOTOVOLTAICS: FUNDAMENTAL AND MANUFACTURABILITY ISSUES |
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| Link | (PDF 4.2 MB) Download Acrobat Reader. |
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| Authors | R. W. Birkmire, W. N. Shafarman, E. Eser, S. S. Hegedus, B. E. McCandless, K. D. Dobson, S. Bowden |
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| Description | This report describes results achieved during phase V of a V-phase subcontract to develop and understand thin film solar cell technology associated to CuInSe2 and related alloys, a-Si and its alloys and CdTe. This includes application of a-Si to c-Si wafer-type cells as well. Modules based on all these thin films are promising candidates to meet DOE long-range efficiency, reliability and manufacturing cost goals. The critical issues being addressed under this program are intended to provide the science and engineering basis for the development of viable commercial processes and to improve module performance. The generic research issues addressed are: 1) quantitative analysis of processing steps to provide information for efficient commercial scale equipment design and operation; 2) device characterization relating the device performance to materials properties and process conditions; 3) development of alloy materials with different bandgaps to allow improved device structures for stability and compatibility with module design; 4) development of improved window/heterojunction layers and contacts to improve device performance and reliability; and 5) evaluation of cell stability with respect to illumination, temperature and ambient and with respect to device structure and module encapsulation. |
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| Venue | Institute of Energy Conversion (U. Delaware), Subcontract No. ADJ-1-30630-12, annual report |
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| Source | University of Delaware |
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| Document Type | Annual Report (Adobe Postscript file) |
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| Resource Date | 04/01/2008 |
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|
| Post Date | 01/14/2008 |
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| Title | FABRICATION AND PHYSICS OF CDTE DEVICES BY SPUTTERING |
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| Link | (PDF 3.8 MB) Download Acrobat Reader. |
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| Authors | A. Compaan, R. W. Collins, V. G. Karpov, D. Giolando |
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| Description | Our effort on device physics has focused on studies of the optical and morphological properties of CdS and CdTe films using spectroscopic ellipsometry. This has been carried out both in situ in real time during the sputter deposition processes and ex situ on films after sputter deposition is interrupted at different stages or after the CdCl2 processing is completed. Other characterization has included EXAFS and high resolution TEM and EDS. Using transparent back contacts we have begun to explore carrier collection through the bifacial response of cells with CdTe layers between 0.7 and 2.3 ?m. We have sought better understanding of the factors controlling growth rates by studying the dependence on gas pressure as well as rf power paying close attention to film morphology and strain. We have explored alternative shunt passivation treatments and have modeled the fundamental physics of ultrathin solar cells. |
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| Venue | University of Toledo, subcontract ZXL-5-44205-01, Annual Report |
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| Source | University of Toledo |
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| Document Type | Annual Report (Adobe Postscript file) |
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| Resource Date | 10/2007 |
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|
| Post Date | 10/25/2007 |
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| Title | CHARACTERIZATION OF THE ELECTRONIC AND CHEMICAL STRUCTURE AT THIN FILM SOLAR CELL INTERFACES |
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| Link | (PDF 1.3 MB) Download Acrobat Reader. |
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| Authors | C. Heske, M. Baer |
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| Description | This project is devoted to deriving the electronic structure of interfaces in Cu(In,Ga)(S,Se)2 and CdTe thin film solar cells. By using a unique combination of spectroscopic methods (photoelectron spectroscopy, inverse photoemission, and X-ray absorption and emission) a comprehensive picture of the electronic (i.e., band alignment in the valence and conduction band) as well as chemical structure can be painted. The work focuses on (a) deriving the bench mark picture for world-record cells, (b) analyze state-of-the-art cells from industrial processes, and (c) aid in the troubleshooting of cells with substandard performance. In the last year, we could draw a complete picture of the chemical and electronic properties of the deeply buried chalcopyrite/back contact interface. For these experiments Cu(In,Ga)Se2 ("CIGSe") and Cu(In,Ga)(S,Se)2 ("CIGSSe")/back contact samples pre-pared by the group of W. Shafarman (Institute of Energy Conversion, University of Delaware) were used. We have found a pronounced chemical interaction between absorber and back contact, namely the formation of MoSe2 (and Mo(S,Se)2) and a "diffusion" of Ga into the Mo layer. In addition, we could derive a tentatively flat valence band alignment at this interface. In addition, we have investigated the CdS/CIGSe interface of samples provided by the National Renewable Energy Laboratory (M. Contreras, R. Noufi), which currently holds the world record for respective solar cell devices in terms of photovoltaic performance. Our results show that, in contrast to earlier measurements on samples from a different source, no pronounced S/Se intermixing at this interface can be observed. |
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| Venue | University of Nevada, Las Vegas, subcontract XXL-5-44205-12, annual report |
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| Source | University of Nevada, Las Vegas |
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| Document Type | Annual Report (Adobe Postscript file) |
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| Resource Date | 08/15/2007 |
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|
| Post Date | 06/22/2007 |
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| Title | CHARACTERIZATION AND ANALYSIS OF CIGS AND CDTE SOLAR CELLS |
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| Link | (PDF 1.3 MB) Download Acrobat Reader. |
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| Author | J. R. Sites |
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| Description | The fundamental work on CIGS cells included an analysis of the expected behavior for submicron thin absorbers. A baseline scenario based on experimental results was compared with conditions where the absorber lifetime and its carrier concentration were reduced by an order of magnitude. Additional calculations compared front-side with back-side illumination, again in the context of experimental results, and calculated several consequences of weak-diode areas and partial shunting, both expected to be of increasing importance for thinner CIGS. Finally, a collaboration with NREL compared the differences between 19.5%-efficient CdZnS/CIGS cells and those made with the conventional CdS buffer.
A major CdTe project in response to the excessive voltage deficit between CdTe and single-crystal cells has been the analysis of strategies to significantly enhance voltage. One strategy recommended for a major experimental effort is an n-i-p structure with an electron reflector before the back contact. Experimentally, CdTe lifetime and current-voltage curves were measured as a function of copper amount used in the back contact, and the expected impact of low lifetimes, including artificially large A-factors, was calculated. Also, experimentally, CdTe cells made with commercially compatible processing were utilized to determine how CdS thickness affects the cell performance parameters. |
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| Venue | Colorado State University subcontract XXL-5-44205-03, Phase II Annual report |
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| Source | Colorado State University |
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| Document Type | Annual Report (Adobe Postscript file) |
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| Resource Date | 04/30/2007 |
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|
| Post Date | 07/19/2006 |
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| Title | FABRICATION AND PHYSICS OF CDTE DEVICES BY SPUTTERING |
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| Link | (PDF 6.7 MB) Download Acrobat Reader. |
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| Authors | A. Compaan, V. G. Karpov, R. W. Collins, D. Giolando |
|---|
| Description | Our efforts on device physics have primarily involved modeling of CdS/CdTe based PV junctions, modeling and verification of device shunting instability, observation and studying the nature of spatial and temporal fluctuations of micro (AFM) currents through CdTe junctions, further studying of piezo-PV coupling, XAFS XES structural chemistry study of CdCl2 treated CdS films, spectral ellipsometry study of surface morphology in the course of structure growth, as well as etching, film structure and device parameters vs. magnetron deposition rate, and device parameters for CdTe thickness below 1 micron. During the first year of this award, we have:
(1) Developed numerical and analytical (field reversal) models explaining all the major facts pertaining to CdTe/CdS device operations,
(2) Developed a quantitative description of shunting instability in thin film PV through the mechanism of dielectric breakdown and verified it experimentally,
(3) Experimentally observed gigantic spatial and temporal fluctuations of micro AFM current and proposed their interpretation based on defect motility in CdTe films,
(4) Developed a new (bending) technique of piezo-PV characterization and observed increase in the open circuit voltage of devices on flexible substrates subject to certain bending; also, observed the piezo-PV coupling in CIGS based materials,
(5) Through XAFS and XES techniques, established the nature of Cu binding in CdS (primarily with S atoms), and effect of substantial compression of certain atomic bonds upon Cu diffusion in CdS,
atomic bonds upon Cu diffusion in CdS,
(6) Established that increase in the magnetron deposition rate by the factor of 2.5 does not hamper the cell performance when the postdeposition treatment is properly optimized,
(7) Experimentally established the relationship between the CdTe film thickness and device efficiency in the range of 2.5 - 0.45 micron, in particular demonstrated high efficiency devices of thickness below 1 micron. |
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| Venue | Subcontract RXL-5-44205-01, University of Toledo, Annual report |
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| Source | University of Toledo |
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| Document Type | Annual Report (Adobe Postscript file) |
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| Resource Date | 07/19/2006 |
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|
| Post Date | 09/07/2006 |
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| Title | CHARACTERIZATION OF THE ELECTRONIC AND CHEMICAL STRUCTURE AT THIN-FILM SOLAR CELL INTERFACES |
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| Link | (PDF 415 KB) Download Acrobat Reader. |
|---|
| Authors | M. Baer, C. Heske |
|---|
| Description |
This project is devoted to deriving the electronic structure of interfaces in Cu(In,Ga)(S,Se)2 and CdTe thin film solar cells. By using a unique combination of spec-troscopic methods (photoelectron spectroscopy, inverse photoemission, and X-ray ab-sorption and emission) a comprehensive picture of the electronic (i.e., band alignment in the valence and conduction band) as well as chemical structure can be painted. The work focuses on (a) deriving the bench mark picture for world-record cells, (b) analyze state-of-the-art cells from industrial processes, and (c) aid in the troubleshooting of cells with substandard performance.
First funds for this project became available in the middle of July 2005. Since then, the workforce of the group was expanded to the size required for this project. The experimental instrumentation at UNLV ? a four-chamber ultra-high vacuum surface analysis and modification system ? was commissioned and put to routine use after its re-location from the University of Würzburg, Germany. In addition, a setup for inverse photoemission was integrated and a new electron analyzer was installed at UNLV to al-low state-of-the-art data acquisition and spectral quality.
Contacts within the Thin Film PV Partnership Program were established to secure a supply of adequate samples. These samples were analyzed both in the lab at UNLV as well as in our beamtimes at the Advanced Light Source, Lawrence Berkeley National Laboratory (Nov. 2 ? 13, 2005 and May 16 ? 23, 2006).
In our first beamtime within this project at the Advanced Light Source we could gather first results with Cu(In,Ga)Se2 samples prepared by NREL. Combined with addi-tional photoemission measurements at UNLV, a detailed picture of the chemical compo-sition at several interfaces and surface of the device structure could be drawn. Also dur-ing the first beamtime at the Advanced Light Source, we conducted first XES measure-ments of CdTe/CdS samples prepared by the group of A. Compaan (University of Toledo). Recently, these synchrotron results could be complemented by initial photo-emission measurements at UNLV of CdTe/CdS thin film stacks provided by X. Wu (NREL).
|
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| Venue | University of Nevada, Las Vegas, subcontract XXL-5-44205-12, annual report |
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| Source | University of Nevada, Las Vegas |
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| Document Type | Annual Report (Adobe Postscript file) |
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| Resource Date | 07/15/2006 |
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|
| Post Date | 06/02/2006 |
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| Title | DOE SOLAR ENERGY TECHNOLOGY PROGRAM FY2005 ANNUAL REPORT |
|---|
| Link | (PDF 5.2 MB) Download Acrobat Reader. |
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| Author | N/A |
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| Description | The majority of the Program?s budget is allocated to PV research and development (R&D). All PV devices convert sunlight directly into electricity. However, there is a variety of materials and processes for creating PV devices, each with its own benefits and drawbacks. The major trade-off is between cost and sunlight-to-electricity conversion efficiency?higher efficiency typically translates into higher cost. Program participants consistently achieve world-record efficiencies for different types of PV, but each effort has the same ultimate goal: optimizing cost and efficiency to produce the least expensive end-use electricity. |
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| Venue | DOE/GO-102006-2314May 2006 |
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| Source | National Renewable Energy Laboratory |
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| Document Type | Annual Report (Adobe Postscript file) |
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| Resource Date | 05/2006 |
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|
| Post Date | 05/18/2006 |
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| Title | CHARACTERIZATION AND ANALYSIS OF CIGS AND CDTE SOLAR CELLS |
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| Link | (PDF 2.5 MB) Download Acrobat Reader. |
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| Author | J. R. Sites |
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| Description | A number of studies relating to the fundamental operation of CIGS and CdTe solar cells were performed during Phase I. In addition, we have worked closely with industrial and NREL partners to evaluate specific cells, expanded our LBIC (light-beam-induced-current) capabilities, and analyzed the effective efficiency to be expected from several commercial thin-film modules. The fundamental work on CIGS cells included a detailed analysis of grain-boundary effects using two-dimensional modeling. It showed that the relatively benign effects observed are best explained by a decrease in the valence band edge in the vicinity of the grain boundary. A second project, which followed earlier work relating spatial grading of CIGS to performance, showed the increasing importance of an electron reflector at the back of the CIGS absorber as it is made progressively thinner. A third project generalized earlier work on the window/absorber conduction band offset to show that there is a general rule governing when a "spike" leads to a distortion of the current-voltage curve. The CdTe studies included a reasonably convincing explanation of the 1.456-eV photoluminescence peak as a copper-oxygen donor complex about 150 meV below the conduction-band minimum. A second project demonstrated how different combinations of absorber lifetime and back-contact barrier lead to different common features seen with CdTe cells. A third project extended stability and uniformity studies to focus on performance differences among cells with graphite, Ag, and Ni back contacts. Finally, a study of current response following voltage steps showed that reversible transients were essentially always present, but their magnitude varied considerably with sample preparation. |
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| Venue | Subcontract ADJ-1-30630-06 |
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| Source | Colorado State University |
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| Document Type | Annual Report (Adobe Postscript file) |
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| Resource Date | 05/2006 |
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|
| Post Date | 04/10/2006 |
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| Title | FULFILLING THE PROMISE OF THIN FILM PV |
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| Link | (PDF 5.5 MB) Download Acrobat Reader. |
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| Author | K. Zweibel |
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| Description | The Thin Film PV Partnership spearheads R&D on emerging thin film PV technologies. Led by the National Center for Photovoltaics and NREL, the Partnership leverages the combined efforts of the thin film PV industry, universities, and government research institutes. |
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| Venue | Brochure excerpt |
|---|
| Source | National Renewable Energy Laboratory |
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| Document Type | Annual Report (Adobe Postscript file) |
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| Resource Date | 04/2006 |
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|
| Post Date | 02/07/2006 |
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| Title | DOE FY2007 CONGRESSIONAL BUDGET REQUEST FOR ENERGY SUPPLY AND CONSERVATION |
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| Link | (PDF 3.4 MB) Download Acrobat Reader. |
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| Author | N/A |
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| Description | Appropriation Account Summary..........................................................................................................3 Appropriation Language ........................................................................................................................7 Energy Efficiency and Renewable Energy ..........................................................................................11 Electricity Delivery & Energy Reliability .........................................................................................511 Nuclear Energy .................................................................................................................................571 Environment, Safety and Health ........................................................................................................705 Legacy Management.........................................................................................................................733 |
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| Venue | The Department of Energy?s FY 2007 Congressional Budget justification is available on the Office of Chief Financial Officer/CFO homepage at http://www.mbe.doe.gov/budget |
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| Source | Department of Energy |
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| Document Type | Annual Report (Adobe Postscript file) |
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| Resource Date | 02/2006 |
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|
| Post Date | 02/01/2006 |
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| Title | THIN FILM PV PARTNERSHIP |
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| Link | (MS Word 393 KB) |
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| Author | K. Zweibel |
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| Description | Objectives Support the near-term transition to first-time manufacturing and commercial introduction of reliable thin-film a-Si, CIS, CdTe, and film silicon modules. Build a technology base upon which these advanced PV technologies can successfully improve manufacturing and continue to progress in terms of performance, reliability, and reduced cost for products meant to compete in the PV marketplace. Sustain innovation to support progress toward ambitious long-term PV cost and performance goals (e.g., 15% modules at under $50/m2 and capable of lasting 30 years) appropriate for cost-competitive PV electricity. Accomplishments Four JOULE milestones were met. Two Technology Partners broke ground on major manufacturing expansions (First Solar 50 MWp, and Uni-Solar 25 MWp). Production of thin films in the United States grew from 12 MWp in 2003 to an estimated >40 MWp in 2005. Future Directions · Continue to address key issues supporting the transition to successful first-time manufacturing or major production expansion in each thin film. · Significantly reduce CIS and CdTe layer thicknesses in cells and support transfer of this to manufacturing. · Direct CdTe research toward higher voltage. · Investigate nano-crystalline bottom cells for thin-film silicon multijunctions.___________________________________________ |
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| Venue | DOE NREL Annual Report |
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| Source | National Renewable Energy Laboratory |
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| Document Type | Annual Report (Word document) |
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| Resource Date | 02/2006 |
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|
| Post Date | 01/25/2006 |
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| Title | PROCESSING MATERIALS, DEVICES AND DIAGNOSTICS FOR THIN FILM PHOTOVOLTAICS: FUNDAMENTAL AND MANUFACTURABILITY ISSUES |
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| Link | (MS Word 16.5 MB) |
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| Author | R. W. Birkmire |
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| Description | CdTe, CIS, CIGS, a-Si, thin Si |
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| Venue | Annual Report to National Renewable Energy Laboratory under Subcontract No. ADJ-1-30630-129/05/04 to 9/04/05 |
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| Source | University of Delaware |
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| Document Type | Annual Report (Word document) |
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| Resource Date | 01/2006 |
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|
| Post Date | 02/01/2006 |
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| Title | MANUFACTURING PROCESS OPTIMIZATION TO IMPROVE STABILITY, YIELD AND EFFICIENCY OF CDS/CDTE PV DEVICES |
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| Link | (MS Word 238 KB) |
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| Author | W. S. Sampath |
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| Description | Under Phase I of the Thin Film Partnership Program, we have made significant progress. During this year, the reproducibility of device efficiency and stability has been demonstrated during long duration operation of the system with a single charge loading for the CdS, CdTe and CdCl2 process. Currently efforts are underway to advance the back contact processing to the same level as outlined in the SOW. In order to accomplish this, a significant upgrade to increase the processing space in our pilot scale system has been designed, fabricated and is currently being installed. A series of detailed studies on the effect of oxygen during the CdCl2 treatment has been performed. Oxygen has been shown to improve the effectiveness of the CdCl2 treatment. Mathematical modeling of a package design has yielded results that show that moisture can be kept from our device for 22 years at 65C temperature with saturated humidity. Hardware to perform steady state photocapacitance (PHCAP) has been designed, built and tested in our laboratory. The effect of processing on the deep states in CdTe devices can be seen quantitatively. Optimum process conditions lead to lower photocapacitance signals. The feasibility of cooling the substrate in vacuum for optimum processing of the back contact has been demonstrated. A large number of experiments have been performed on laser scribing of CdS/CdTe films. Mechanical scribing has yielded the lowest contact resistance between the scribed region and the metallization, to date. Researchers at National Starch and Chemicals (NSC) have performed many experiments to screen print carbon, nickel and silver films in patterns. The adhesion of these films was tested according to ASTM 3359B and achieved a 5B or "excellent" rating. |
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| Venue | September 2005 - January 2006 Thin Film Partnership Program Subcontract XXL-5-44205-02 |
|---|
| Source | Colorado State University |
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| Document Type | Annual Report (Word document) |
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| Resource Date | 01/2006 |
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|
| Post Date | 12/27/2005 |
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| Title | DEEP ELECTRONIC STATES IN CDTE SOLAR CELLS DETECTED WITH ADMITTANCE TECHNIQUES |
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| Link | (MS Word 81 KB) |
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| Author | F. H. Seymour |
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| Description | Deep electronic states (DES) in the absorber layer of thin film polycrystalline CdTe solar cells are believed to be limiting their energy conversion efficiency. Admittance spectroscopy and capacitance transient techniques were applied with a custom-built temperature stage to detect and characterize these DES. CdTe solar cells obtained from two sources that had post-deposition back contact treatments with and without Cu and CdCl2 were studied. DES were detected with activation energies ranging from 0.13 eV to 0.83 eV. One hole trap signature with Ea~0.15 eV was detected in all four cell categories in different concentrations and was attributed to a combination of and the chlorine A-center complex defects. A second hole trap signature with Ea~0.35 eV and detected only in Cu treated cells was attributed to the copper substitutional defect. Analysis of current density voltage temperature data indicates that the defect might be responsible for the improved JSC observed in the CdCl2 treated cells. |
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| Venue | DOE Solar Review 2005 |
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| Source | Colorado School of Mines, Golden, CO |
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| Document Type | Annual Report (Word document) |
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| Resource Date | 12/2005 |
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|
| Post Date | 12/27/2005 |
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| Title | THIN CDTE SOLAR CELLS WITH HIGH THROUGHPUT PROCESSING |
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| Link | (MS Word 68 KB) |
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| Author | B. E. McCandless |
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| Description | Progress towards reducing CdTe film thickness and increasing performance and processing throughput for vapor transport (VT) deposited CdTe/CdS solar cells is highlighted. VT devices with 5-7 mm thick CdTe deposited on moving substrates at 9 mm/min using a 20 min vapor CdCl2 treatment at 415ºC achieved Voc up to 840 mV and h > 13%. Devices with h = 11% were obtained with 2 min CdCl2 treatments at 465ºC. For cells with CdTe thickness ~1.5 mm, h >10% was obtained. Voc and FF decreased for cells with CdTe deposited at >80 mm/min and for cells with mm CdTe. Devices using transparent ZnTe contacts have similar performance to those with opaque contacts and are being used to separate back contact and primary junction effects. |
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| Venue | 2005 DOE Solar Review |
|---|
| Source | University of Delaware |
|---|
| Document Type | Annual Report (Word document) |
|---|
| Resource Date | 12/2005 |
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|
| Post Date | 11/11/2005 |
|---|
| Title | POLYCRYSTALLINE THIN FILM DEVICE DEGRADATION STUDIES |
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| Link | (PDF 85 KB) Download Acrobat Reader. |
|---|
| Author | D. Albin |
|---|
| Description | Oxygen during vapor CdCl2 (VCC) treatments significantly reduced resistive shunts observed in CdS/CdTe polycrystalline devices using thinner CdS layers during 100 °C, open-circuit, 1-sun accelerated stress testing. Cu oxidation resulting from the reduction of various trace oxides present in as-grown and VCC treated films is the proposed mechanism by which Cu diffusion, and subsequent shunts are controlled. Graphite paste layers between metallization and CdTe behave like diffusion barriers and similarly benefit device stability. Ni-based contacts form a protective Ni2Te3 intermetallic layer that reduces metal diffusion but degrades performance through increased series resistance. |
|---|
| Venue | DOE Solar Review Meeting 2005 paper |
|---|
| Source | National Renewable Energy Laboratory |
|---|
| Document Type | Annual Report (Adobe Postscript file) |
|---|
| Resource Date | 11/10/2005 |
|---|
|
| Post Date | 11/11/2005 |
|---|
| Title | DEEP ELECTRONIC STATES IN CDTE SOLAR CELLS DETECTED WITH ADMITTANCE TECHNIQUES |
|---|
| Link | (MS Word 74 KB) |
|---|
| Author | F. H. Seymour |
|---|
| Description | Deep electronic states (DES) in the absorber layer of thin film polycrystalline CdTe solar cells are believed to be limiting their energy conversion efficiency. Admittance spectroscopy and capacitance transient techniques were applied with a custom-built temperature stage to detect and characterize these DES. CdTe solar cells obtained from two sources that had post-deposition back contact treatments with and without Cu and CdCl2 were studied. DES were detected with activation energies ranging from 0.13 eV to 0.83 eV. One hole trap signature with Ea~0.15 eV was detected in all four cell categories in different concentrations and was attributed to a combination of and the chlorine A-center complex defects. A second hole trap signature with Ea~0.35 eV and detected only in Cu treated cells was attributed to the copper substitutional defect. Analysis of current density voltage temperature data indicates that the defect might be responsible for the improved JSC observed in the CdCl2 treated cells. |
|---|
| Venue | DOE Solar Review 2005 |
|---|
| Source | Colorado School of Mines, Golden, CO |
|---|
| Document Type | Annual Report (Word document) |
|---|
| Resource Date | 11/2005 |
|---|
|
| Post Date | 11/17/2005 |
|---|
| Title | UNDERSTANDING THE PHYSICS OF CDS-BASED PV: BAND DIAGRAM, INTERFACES, AND NONUNIFORMITIES |
|---|
| Link | (MS Word 120 KB) |
|---|
| Author | V. G. Karpov |
|---|
| Description | Our recent discovery of piezo-PV coupling together with other indicative evidence suggest an adequate band diagram for CdS based thin-film PV. The proposed model is solved analytically leading to numerous predictions that include lack of the carrier collection from CdS, buffer layer effects, and others. This understanding points at new pathways for device improvement. |
|---|
| Venue | DOE Solar Review 2005 |
|---|
| Source | University of Toledo |
|---|
| Document Type | Annual Report (Word document) |
|---|
| Resource Date | 11/2005 |
|---|
|
| Post Date | 04/05/2005 |
|---|
| Title | ADVANCED PROCESSING OF CDTE- AND
CUIN1-XGAXSE2- BASED SOLAR CELLS |
|---|
| Link | (PDF 584 KB) Download Acrobat Reader. |
|---|
| Authors | C. S. Ferekides, D. Morel |
|---|
| Description | CdTe CSS and CIGS sputtering |
|---|
| Venue | NDJ-2-30630-18 PHASE II |
|---|
| Source | University of South Florida, Tampa |
|---|
| Document Type | Annual Report (Adobe Postscript file) |
|---|
| Resource Date | 03/2005 |
|---|
|
| Post Date | 02/17/2005 |
|---|
| Title | PROCESSING MATERIALS, DEVICES AND DIAGNOSTICS FOR THIN FILM PHOTOVOLTAICS |
|---|
| Link | (MS Word 7.7 MB) |
|---|
| Authors | R. W. Birkmire, S. S. Hegedus, B. E. McCandless, W. N. Shafarman, et al. |
|---|
| Description | |
|---|
| Venue | ADJ-1-30630-12 9/05/03 to 9/04/04 |
|---|
| Source | University of Delaware |
|---|
| Document Type | Annual Report (Word document) |
|---|
| Resource Date | 10/2004 |
|---|
|
| Post Date | 01/18/2004 |
|---|
| Title | STABILITY, YIELD AND EFFICIENCY OF CDS/CDTE DEVICES |
|---|
| Link | (MS Word 31 KB) |
|---|
| Author | W. S. Sampath |
|---|
| Description | One-page summary of 2004 accomplishments |
|---|
| Venue | 2004 Summary Annual Report for NREL Program; Subcontract No. ADJ-1-30630-07 to Colorado State University |
|---|
| Source | Colorado State University |
|---|
| Document Type | Annual Report (Word document) |
|---|
| Resource Date | 10/2004 |
|---|
|
| Post Date | 02/09/2005 |
|---|
| Title | RESEARCH LEADING TO HIGH THROUGHPUT MANUFACTURING OF THIN-FILM CDTE PV MODULES |
|---|
| Link | (MS Word 7.8 MB) |
|---|
| Author | R. C. Powell |
|---|
| Description | First Solar is actively commercializing CdTe-based thin film photovoltaics. During the past year major additions of production capability have been completed as well as process improvements to achieve higher throughput and efficiency and greater durability. This report presents the results of phase II of the subcontract entitled "Research Leading to High Throughput Manufacturing of Thin-Film CdTe PV Modules". The subcontract supports several important aspects needed to for high volume manufacturing of high efficiency modules including exploration of large area advanced front contact window layers, improvements of the semiconductor deposition system, advancement in understanding of post deposition processing steps and accelerated life testing methods, and progress to the environmental, health and safety programs. |
|---|
| Venue | Annual subcontract report
mailto:Doug Rose |
|---|
| Source | First Solar, Toledo, OH |
|---|
| Document Type | Annual Report (Word document) |
|---|
| Resource Date | 09/27/2004 |
|---|
|
| Post Date | 02/08/2005 |
|---|
| Title | STUDIES OF BASIC ELECTRONIC PROPERTIES OF CDTE-BASED SOLAR CELLS & THEIR EVOLUTION DURING PROCESSING & STRESS |
|---|
| Link | (PDF 3.0 MB) Download Acrobat Reader. |
|---|
| Authors | V. Kaydanov, T. Ohno |
|---|
| Description | We emphasize the relation between composition, structural and electronic material properties and various processing procedures as well as the microscopic mechanisms responsible for the cell performance and its degradation. |
|---|
| Venue | ADJ-2-30630-05 |
|---|
| Source | Colorado School of Mines, Golden, CO |
|---|
| Document Type | Annual Report (Adobe Postscript file) |
|---|
| Resource Date | 11/2003 |
|---|
|
| Post Date | 01/21/2005 |
|---|
| Title | DEVICE PHYSICS OF THIN-FILM POLYCRYSTALLINE CELLS AND MODULES |
|---|
| Link | (MS Word 26 KB) |
|---|
| Author | J. R. Sites |
|---|
| Description | Work was performed at Colorado State University on basic measurements of CIGS and CdTe solar cells fabricated at a number of collaborating laboratories. The goal is to quantitatively deduce the loss mechanisms in a number of these cells, and to make appropriate comparisons that illuminate where progress is being made. |
|---|
| Venue | Summary Report for 2003, Subcontract ADJ-1-30630-06 |
|---|
| Source | Colorado State University |
|---|
| Document Type | Annual Report (Word document) |
|---|
| Resource Date | 10/2003 |
|---|
|
| Post Date | 02/02/2005 |
|---|
| Title | 2003 DOE PV PEER REVIEW |
|---|
| Link | (PDF 716 KB) Download Acrobat Reader. |
|---|
| Author | N/A |
|---|
| Description | Review of DOE PV activities in 2003 |
|---|
| Venue | US DOE EERE |
|---|
| Source | US DOE |
|---|
| Document Type | Annual Report (Adobe Postscript file) |
|---|
| Resource Date | 09/30/2003 |
|---|
|
| Post Date | 02/09/2005 |
|---|
| Title | RESEARCH LEADING TO HIGH THROUGHPUT MANUFACTURING OF THIN-FILM CDTE PV MODULES PHASE I |
|---|
| Link | (MS Word 5.7 MB) |
|---|
| Author | R. C. Powell |
|---|
| Description | The subcontract supports several important aspects needed to begin high volume manufacturing including further development of the semiconductor deposition reactor, advancement of accelerated life testing methods and understanding, and improvements to the environmental, health and safety programs. |
|---|
| Venue | NREL report RDJ-2-30630-20 |
|---|
| Source | First Solar, Toledo, OH |
|---|
| Document Type | Annual Report (Word document) |
|---|
| Resource Date | 09/27/2003 |
|---|
|
| Post Date | 02/09/2005 |
|---|
| Title | PROCESSING MATERIALS, DEVICES AND DIAGNOSTICS FOR THIN FILM PHOTOVOLTAICS: FUNDAMENTAL AND MANUFACTURABILITY ISSUES |
|---|
| Link | (MS Word 4.6 MB) |
|---|
| Authors | R. W. Birkmire, S. S. Hegedus, B. E. McCandless, W. N. Shafarman, et al. |
|---|
| Description | |
|---|
| Venue | Annual report ADJ-1-30630-12 |
|---|
| Source | University of Delaware |
|---|
| Document Type | Annual Report (Word document) |
|---|
| Resource Date | 09/04/2003 |
|---|
|
| Post Date | 02/10/2005 |
|---|
| Title | DEVICE PHYSICS OF THIN-FILM POLYCRYSTALLINE CELLS AND MODULES |
|---|
| Link | (MS Word 2.9 MB) |
|---|
| Author | J. R. Sites |
|---|
| Description | The goal has been to quantitatively deduce the loss mechanisms in a number of these cells, and to make appropriate comparisons that illuminate where progress is being made. |
|---|
| Venue | Phase II September 2002 - August 2003 ADJ-1-30630-06 |
|---|
| Source | Colorado State University |
|---|
| Document Type | Annual Report (Word document) |
|---|
| Resource Date | 09/2003 |
|---|
|
| Post Date | 02/10/2005 |
|---|
| Title | THE FABRICATION AND PHYSICS OF HIGH-E±CIENCY CDTE THIN-FILM SOLAR CELLS |
|---|
| Link | (PDF 3.9 MB) Download Acrobat Reader. |
|---|
| Author | A. Compaan |
|---|
| Description | Our efforts on cell fabrication have primarily involved the use of magnetron sputtering for deposition. In addition, we have developed and used novel electrochemical treatments at the stage of finishing the devices deposited by other techniques: vapor transfer deposition (VTD) and close space sublimation (CSS), both made at First Solar, LLC. |
|---|
| Venue | NDJ-1-30630-02 September 1, 2002 to August 31, 2003 |
|---|
| Source | University of Toledo |
|---|
| Document Type | Annual Report (Adobe Postscript file) |
|---|
| Resource Date | 09/2003 |
|---|
|
| Post Date | 03/04/2005 |
|---|
| Title | PROCESSING MATERIALS, DEVICES AND DIAGNOSTICS FOR THIN FILM PHOTOVOLTAICS: FUNDAMENTAL AND MANUFACTURABILITY ISSUES |
|---|
| Link | (MS Word 4.5 MB) |
|---|
| Author | R. W. Birkmire |
|---|
| Description | |
|---|
| Venue | ADJ-1-30630-12 9/05/02 to 9/04/03 |
|---|
| Source | University of Delaware |
|---|
| Document Type | Annual Report (Word document) |
|---|
| Resource Date | 09/2003 |
|---|
|
| Post Date | 03/03/2005 |
|---|
| Title | PROCESSING, MATERIALS, DEVICES AND DIAGNOSTICS FOR THIN-FILM PHOTOVOLTAICS: FUNDAMENTAL AND MANUFACTURABILITY ISSUES |
|---|
| Link | (MS Word 37 KB) |
|---|
| Author | R. W. Birkmire |
|---|
| Description | |
|---|
| Venue | PV Program Contract Summary Report Thin-film PV Partnership Program |
|---|
| Source | University of Delaware |
|---|
| Document Type | Annual Report (Word document) |
|---|
| Resource Date | 09/2003 |
|---|
|
| Post Date | 03/03/2005 |
|---|
| Title | DEVICE PHYSICS OF THIN-FILM POLYCRYSTALLINE CELLS AND MODULES |
|---|
| Link | (MS Word 2.9 MB) |
|---|
| Author | J. R. Sites |
|---|
| Description | |
|---|
| Venue | ADJ-1-30630-06 |
|---|
| Source | Colorado State University |
|---|
| Document Type | Annual Report (Word document) |
|---|
| Resource Date | 09/2003 |
|---|
|
| Post Date | 02/08/2005 |
|---|
| Title | ADVANCED PROCESSING OF CDTE- AND CUIN1-XGAXSE2 |
|---|
| Link | (PDF 1.9 MB) Download Acrobat Reader. |
|---|
| Authors | C. S. Ferekides, D. Morel |
|---|
| Description | This project addresses two thin film technologies CdTe and CIGS. The CdTe component of the project has three task areas. These are: development of simplified processing for the fabrication of CdTe solar cells correlation of the long term stability with process/device characteristics. |
|---|
| Venue | Phase I Final Report to NREL NDJ-2-30630-18 |
|---|
| Source | University of South Florida, Tampa |
|---|
| Document Type | Annual Report (Adobe Postscript file) |
|---|
| Resource Date | 2003 |
|---|
|
| Post Date | 02/10/2005 |
|---|
| Title | THE FABRICATION AND PHYSICS OF HIGH-EFFICIENCY CDTE THIN-FILM SOLAR CELLS |
|---|
| Link | (PDF 3.1 MB) Download Acrobat Reader. |
|---|
| Author | A. Compaan |
|---|
| Description | |
|---|
| Venue | NDJ-1-30630-02 September 1, 2001 to August 31, 2002 |
|---|
| Source | University of Toledo |
|---|
| Document Type | Annual Report (Adobe Postscript file) |
|---|
| Resource Date | 09/2002 |
|---|
|
| Post Date | 02/15/2005 |
|---|
| Title | DEVICE PHYSICS OF THIN-FILM POLYCRYSTALLINE CELLS AND MODULES |
|---|
| Link | (MS Word 1.2 MB) |
|---|
| Author | J. R. Sites |
|---|
| Description | Work has been performed at Colorado State University on basic measurements of CdTe and CI(G)S solar cells fabricated at a number of collaborating laboratories. The goal has been to quantitatively deduce the loss mechanisms in a number of these cells, and to make appropriate comparisons that illuminate where progress is being made. Special emphasis was given to the differences in CdTe cells, both as-deposited and after elevated-temperature stress, that result from variations in the amount of back-contact copper. The second area of study has been further development of small-spot measurement of micro-nonuniforities, including those that develop during temperature stress. The facility focuses a laser beam onto a solar cell with 1-mm beam size, 1-mm resolution and repeatability, and one-sun intensity. The third task has been the determination of defect-state densities in CIGS cells by low-temperature capacitance measurements. Emphasis has been given to the comparisons between CIGS absorbers fabricated by different techniques and among different strategies for the buffer between absorber and transparent contact. The final task area has been numerical simulations of CdTe and CI(G)S cells. Replication of experimental data has been successful in both cases. The CdTe CIGS studies have illuminated the effects of thickness variations in the CdS and CdTe layers, while more recent CIGS studies have shown the impact of the CdS/CIGS conduction band offset on light/dark superposition. |
|---|
| Venue | Subcontract ADJ-1-30630-06 Phase I September 2001 - August 2002 |
|---|
| Source | Colorado State University |
|---|
| Document Type | Annual Report (Word document) |
|---|
| Resource Date | 09/2002 |
|---|
|
| Post Date | 02/08/2005 |
|---|
| Title | DEVICE PHYSICS OF THIN-FILM POLYCRYSTALLINE CELLS AND MODULES |
|---|
| Link | (MS Word 1.2 MB) |
|---|
| Author | J. R. Sites |
|---|
| Description | Work has been performed at Colorado State University on basic measurements of CdTe and CI(G)S solar cells fabricated at a number of collaborating laboratories. The goal has been to quantitatively deduce the loss mechanisms in a number of these cells, and to make appropriate comparisons that illuminate where progress is being made. Special emphasis was given to the differences in CdTe cells, both as-deposited and after elevated-temperature stress, that result from variations in the amount of back-contact copper. |
|---|
| Venue | NREL Phase I September 2001 - August 2002 Subcontract ADJ-1-30630-06 |
|---|
| Source | Colorado State University |
|---|
| Document Type | Annual Report (Word document) |
|---|
| Resource Date | 09/2002 |
|---|
|
| Post Date | 03/03/2005 |
|---|
| Title | ADVANCED PROCESSING OF CDTE- AND CUIN1-XGAXSE2- BASED SOLAR CELLS |
|---|
| Link | (PDF 1.9 MB) Download Acrobat Reader. |
|---|
| Authors | C. S. Ferekides, D. Morel |
|---|
| Description | |
|---|
| Venue | NDJ-2-30630-18 |
|---|
| Source | University of South Florida, Tampa |
|---|
| Document Type | Annual Report (Adobe Postscript file) |
|---|
| Resource Date | 2002 |
|---|
|
| Post Date | 05/30/2006 |
|---|
| Title | ADVANCED PROCESSING OF CDTE- AND
CUIN1-XGAXSE2 CELLS |
|---|
| Link | (PDF 1.0 MB) Download Acrobat Reader. |
|---|
| Authors | C. S. Ferekides, D. Morel |
|---|
| Description | This is the final report for the 3-year project with subcontract # NDJ-2-30630-18. The CdTe section of the report is organized in 2 major sections: (a) a summary of the activities and major results obtained during the first two 2 years (covered in Annual Reports I & II), and (b) activities for year 3. Additional details will be provided within the subsequent sections. |
|---|
| Venue | NDJ-2-30630-18 |
|---|
| Source | University of South Florida, Tampa |
|---|
| Document Type | Final Report (Adobe Postscript file) |
|---|
| Resource Date | 05/2006 |
|---|
|
| Post Date | 05/11/2005 |
|---|
| Title | DEVICE PHYSICS OF THIN-FILMPOLYCRYSTALLINE CELLS AND MODULES SUMMARY REPORT FOR 2004, SUBCONTRACT ADJ-1-30630-06 |
|---|
| Link | (MS Word 27 KB) |
|---|
| Author | J. R. Sites |
|---|
| Description | Task 1: Whole-cell analysis. The J-V distortions in CIGS cells due to an excessive spike in the conduction-band offset have been broadly documented and explained. The effects of a copper deficiency in the CdTe back contact have been similarly documented and explained. The process for systematic quantification of individual loss mechanisms in both types of cells has been refined and made more routine. Task 2: Highly focused light spot. Light-beam-induced-current (LBIC) measurements have shown that changes is CdTe cell response essentially always occur in localized regions. Additional refinements in cell-mounting, measurement, and display techniques have also made LBIC measurements more routine. Task 3: Defect-states. Low-temperature capacitance measurements with CIGS cells were used to compare absorbers fabricated by evaporation and by selenization, and to compare CdS and Cd-partial-electolyte buffer layers. CdTe photoluminescence was used to identify a key defect state as a copper/oxygen donor complex approximately 150 meV below the conduction band. Task 4. Numerical simulation. One project documented the limitation to cell voltage due to the CdS/CIGS conduction-band offset. A second showed that grading profiles in standard-thickness CIGS absorbers lead at best to only a modest increase in cell efficiency. A third project showed that a broad range of features seen in CdTe quantum-efficiency measurements can be explained with a simple three-layer model. |
|---|
| Venue | ADJ-1-30630-06 |
|---|
| Source | Colorado State University |
|---|
| Document Type | Final Report (Word document) |
|---|
| Resource Date | 05/2005 |
|---|
|
| Post Date | 05/11/2005 |
|---|
| Title | DEVICE PHYSICS OF THIN-FILM POLYCRYSTALLINE CELLS AND MODULES |
|---|
| Link | (PDF 3.0 MB) Download Acrobat Reader. |
|---|
| Author | J. R. Sites |
|---|
| Description | The first area of study has been whole-cell analysis. Individual projects have included development of more effective separation of losses, the role of copper incorporation and migration with CdTe cells, the current-voltage consequences of the conduction-band offset in CdS/CIGS cells, alternative buffers for CIGS cells, and the development of the CurVA software for analysis of current-voltage curves. The second area of study has been the use of a highly focused light spot (LBIC) to investigate spatial variations in polycrystalline solar cells. The local effects of elevated- temperature stress on CdTe cells has received the most attention, but we have also demonstrated that LBIC can be combined with other non-uniformity studies on the same cell and that it is possible to partially construct the J-V curve at individual local positions. The third task has been the study of defect-states. With CIGS cells, we used lowtemperature capacitance measurements to compare absorbers fabricated by evaporation with those made by selenization and to compare CdS buffer layers with the Cd-partialelectrolyte. For CdTe, photoluminescence from single crystals with controlled introduction of copper and oxygen has been compared with that from solar-cell material. The final task area has been numerical simulation. We have defined and advocated a set of baseline parameters for CIGS and CdTe cells. Specific projects have included explanations of apparent quantum- and collection-efficiency effects, the impact of conduction-band offset on current-voltage curves, the effects of absorber grading in CIGS cells, and the 2-D analysis of grain-boundary effects. |
|---|
| Venue | ADJ-1-30630-06 September 2001 - October 2004 |
|---|
| Source | Colorado State University |
|---|
| Document Type | Final Report (Adobe Postscript file) |
|---|
| Resource Date | 05/2005 |
|---|
|
| Post Date | 01/03/2006 |
|---|
| Title | ENERGY PAY-BACK AND LIFE CYCLE CO2 EMISSIONS OF THE BOS IN AN OPTIMIZED 3.5 MW PV INSTALLATION |
|---|
| Link | tepbos2005 |
|---|
| Author | J. Mason |
|---|
| Description | This study is a life-cycle analysis of the balance of system (BOS) components of the 3.5 MWp multi-crystalline PV installation at Tucson Electric Power's (TEP) Springerville, AZ field PV plant. TEP instituted an innovative PV installation program guided by design optimization and cost minimization. The advanced design of the PV structure incorporated the weight of the PV modules as support, thereby eliminating the need for concrete foundations. The estimate of the life-cycle energy requirements embodied in the BOS is 543 MJ/m2, a 71% reduction from those of an older central plant; the corresponding life-cycle greenhouse gas emissions are 29 kg CO2-eq. /m2. From field measurements, the energy payback time (EPT) of the BOS is 0.21 years for the actual location of this plant, and 0.37 years for average US insolation/temperature conditions. This is a great improvement from the EPT of 2 years estimated for an older central plant. The total cost of the balance of system components was $940 US per kWp of installed PV, another milestone in improvement. These results were verified with data from different databases and further tested with sensitivity- and data-uncertainty analyses. Key Words: PV plant; balance of system; life cycle assessment, energy payback, GHG emissions |
|---|
| Venue | website |
|---|
| Source | Tucson Electric |
|---|
| Document Type | Final Report (Hypertext link) |
|---|
| Resource Date | 2005 |
|---|
|
| Post Date | 04/21/2005 |
|---|
| Title | PVACCEPT |
|---|
| Link | PVACCEPT |
|---|
| Author | N/A |
|---|
| Description | PVACCEPT is a German-Italian research project, which was funded by the European Commission within the programme "Innovation and Small and Medium Sized Enterprises". The project aimed at designing and developing marketable solar modules for electricity generation, which are designed in a way to enable their sensitive and inconspicuous integration into old buildings, historical sites, and protected landscapes. The project has officially started on 1st July 2001, and is concluded since 31st December 2004. |
|---|
| Venue | |
|---|
| Sources | University of Arts, Berlin; University of Siena |
|---|
| Document Type | Final Report (Hypertext link) |
|---|
| Resource Date | 12/2004 |
|---|
|
| Post Date | 02/08/2005 |
|---|
| Title | DEVICE PHYSICS OF THIN-FILM POLYCRYSTALLINE CELLS AND MODULES |
|---|
| Link | (PDF 3.0 MB) Download Acrobat Reader. |
|---|
| Author | J. R. Sites |
|---|
| Description | Work has been performed at Colorado State University on basic measurements of CIGS and CdTe solar cells fabricated at a number of collaborating laboratories. The goal has been to explain several features seen in these measurements and quantitatively assess their impact on device performance. |
|---|
| Venue | Subcontract ADJ-1-30630-06 Final Report to NREL |
|---|
| Sources | Colorado State University; National Renewable Energy Laboratory |
|---|
| Document Type | Final Report (Adobe Postscript file) |
|---|
| Resource Date | 10/2004 |
|---|
|
| Post Date | 02/08/2005 |
|---|
| Title | STABILITY, YIELD AND EFFICIENCY OF CDS/CDTE DEVICES |
|---|
| Link | (PDF 632 KB) Download Acrobat Reader. |
|---|
| Authors | K. L. Barth, R. A. Enzenroth, W. S. Sampath |
|---|
| Description | Major results have been shown in the areas of device characterization, experimental infrastructure improvements and processing larger area substrates. |
|---|
| Venue | NREL ADJ-1-30630-07 |
|---|
| Source | Colorado State University |
|---|
| Document Type | Final Report (Adobe Postscript file) |
|---|
| Resource Date | 10/2004 |
|---|
|
| Post Date | 02/04/2005 |
|---|
| Title | STUDY OF POTENTIAL COST REDUCTIONS RESULTING FROM SUPER-LARGE-SCALE MANUFACTURING OF PV MODULES |
|---|
| Link | (PDF 768 KB) Download Acrobat Reader. |
|---|
| Authors | R. Arya, M. Keshner, K. Zweibel |
|---|
| Description | Technology investments by the U.S. government Dept. of Energy, National Renewable Energy Lab (NREL) and others over the past 30 years have positioned the Solar Energy industry to undergo an inflection. The technology is now very close to good enough. The key issue is cost. |
|---|
| Venue | NREL final report NREL/SR-520-36846 Subcontract No. ADJ-3-33631-01 |
|---|
| Sources | Hewlett Packard; National Renewable Energy Laboratory |
|---|
| Document Type | Final Report (Adobe Postscript file) |
|---|
| Resource Date | 10/2004 |
|---|
|
| Post Date | 03/11/2005 |
|---|
| Title | LEARNING FROM THE SUN |
|---|
| Link | (PDF 3.3 MB) Download Acrobat Reader. |
|---|
| Authors | E. A. Alsema, G. J. Schaeffer, et al. |
|---|
| Description | Analysis of the use of experience curves for energy policy purposes: The case of photovoltaic power. Final report of the Photex project |
|---|
| Venue | ECN-C--04-035 |
|---|
| Source | Photex |
|---|
| Document Type | Final Report (Adobe Postscript file) |
|---|
| Resource Date | 08/2004 |
|---|
|
| Post Date | 02/11/2005 |
|---|
| Title | WORKSHOP ON LIFE CYCLE ANALYSIS AND RECYCLING OF SOLAR MODULES - THE "WASTE" CHALLENGE |
|---|
| Link | (PDF 12.5 MB) Download Acrobat Reader. |
|---|
| Author | A. Jager-Waldau |
|---|
| Description | First, to rise the awareness of the Photovoltaic Community about the European Directives 2002/96/EC on waste electrical and electronic equipment (WEEE) and 2002/95/EC on the restriction of the use of certain hazardous substances in electrical and electronic equipment (ROHS), which have to be implemented by the Member States in 2004. These directives will have a significant impact on the PV industry, not only because the future waste classification of PV modules is an important issue, but also the sustainability and the green image of the PV industry as a whole has to be considered. The second focus was on Life Cycle Assessment the correct evaluation of External Costs and the Recycling of Solar Modules, which will help to avoid these problems. The workshop gave an overview about the current scientific and political discussion, identified problems and showed the way for possible solutions. |
|---|
| Venue | European Commission EUR 21101 EN |
|---|
| Source | European Commission Joint Research Centre |
|---|
| Document Type | Final Report (Adobe Postscript file) |
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| Resource Date | 03/19/2004 |
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|
| Post Date | 02/10/2005 |
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| Title | THE FABRICATION AND PHYSICS OF HIGH-E±CIENCY CDTE THIN-FILM SOLAR CELLS |
|---|
| Link | (PDF 2.2 MB) Download Acrobat Reader. |
|---|
| Authors | A. Compaan, et al. |
|---|
| Description | Cell structure and fabrication, cell modelling, and characterization of materials and devices. |
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| Venue | NDJ-1-30630-02 September 1, 2001 to August 31, 2004 |
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| Source | University of Toledo |
|---|
| Document Type | Final Report (Adobe Postscript file) |
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| Resource Date | 01/2004 |
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|
| Post Date | 02/07/2005 |
|---|
| Title | PV STATUS REPORT 2003 |
|---|
| Link | (PDF 671 KB) Download Acrobat Reader. |
|---|
| Author | A. Jager-Waldau |
|---|
| Description | Research, Solar Cell Production and Market Implementation in Japan, USA and the European Union. |
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| Venue | European Commission JRC EUR 20850EN |
|---|
| Source | Institute for Environment and Sustainability |
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| Document Type | Final Report (Adobe Postscript file) |
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| Resource Date | 09/2003 |
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|
| Post Date | 02/07/2005 |
|---|
| Title | NUMERICAL MODELING AS A TOOL FOR ANALYZING THIN-FILM SOLAR CELLS AND INTERPRETING DEVICE AND MATERIAL CHARACTERIZATION MEASUREMENTS |
|---|
| Link | (PDF 116 KB) Download Acrobat Reader. |
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| Author | J. L. Gray |
|---|
| Description | Detailed numerical modeling has proved to be a useful tool in developing many of the current PV technologies such as single crystal Si, GaAs, ? -Si, CdTe, and CIS, to name a few. The purpose of this work is to continue development of ADEPT (A Device Emulation Program and Tool) ? primarily to integrate it with MatLab™. |
|---|
| Venue | NREL Report, contract XAK-8-17619-36 |
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| Source | Purdue |
|---|
| Document Type | Final Report (Adobe Postscript file) |
|---|
| Resource Date | 2003 |
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|
| Post Date | 11/11/2005 |
|---|
| Title | TELLURIUM AVALAIBILITY FOR LARGE SCALE PV |
|---|
| Link | (MS Word 140 KB) |
|---|
| Author | J. Guilinger |
|---|
| Description | Analysis of sources of tellurium for multi-GWp PV production |
|---|
| Venue | Report to NREL |
|---|
| Source | World Industrial Minerals |
|---|
| Document Type | Final Report (Word document) |
|---|
| Resource Date | 2000 |
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|
| Post Date | 02/11/2005 |
|---|
| Title | ENVIRONMENTAL ASPECTS OF PV POWER SYSTEMS |
|---|
| Link | (PDF 278 KB) Download Acrobat Reader. |
|---|
| Authors | E. A. Alsema, E. Nieuwlaar |
|---|
| Description | An expert workshop was held as part of the International Energy Agency Photovoltaic Power Systems Implementing Agreement Programme, to address these environmental aspects of PV power systems. The objectives of the workshop were: Review/overview of issues and approaches regarding environmental aspects of PV power systems; Enhanced clarity and consensus regarding well-known aspects like Energy Pay-Back Time; Identification of issues of environmental importance regarding PV power systems ('hot spots'); Identification of issues requiring further attention ('white spots'); |
|---|
| Venue | IEA PVPS Task 1 Workshop 25-27 June 1997 Utrecht, The Netherlands Report no. 97072 |
|---|
| Source | Utrecht University |
|---|
| Document Type | Final Report (Adobe Postscript file) |
|---|
| Resource Date | 12/1997 |
|---|
|
| Post Date | 02/11/2005 |
|---|
| Title | ENVIRONMENTAL ASPECTS OF SOLAR CELL MODULES |
|---|
| Link | (PDF 466 KB) Download Acrobat Reader. |
|---|
| Author | E. A. Alsema |
|---|
| Description | multicrystalline silicon, amorphous silicon, cadmium telluride and copper indium selenide are reviewed with special attention to future expected technology developments. For each module type an assessment is made of the potential environmental impacts in case of large scale implementation of the technology. In principle the entire module life cycle is taken into consideration: from resource mining, via module production and module utilization until module decommissioning and waste handling. In the report for each module type the following aspects are discussed: energy requirements and energy pay-back time, material requirements and resource depletion, environmental emissions, waste handling, possibilities for recycling of modules, occupational health and safety and external safety. |
|---|
| Venue | Report nr. 96074 ISBN 90-73958-17-2 Netherlands Agency for Energy and the Environment (NOVEM) |
|---|
| Source | Utrecht University |
|---|
| Document Type | Final Report (Adobe Postscript file) |
|---|
| Resource Date | 08/1996 |
|---|
|
Back to Top Quarterly Reports
| Post Date | 05/09/2005 |
|---|
| Title | STABILITY, YIELD AND EFFICIENCY OF CDS/CDTE DEVICES |
|---|
| Link | (MS Word 70 KB) |
|---|
| Author | W. S. Sampath |
|---|
| Description | During this quarter, we have progressed on the tasks outlined in our SOW for Phase I. Reproducibility of device efficiency and stability has been demonstrated during long duration operation of the system with a single charge loading for the CdS, CdTe and CdCl2 process. Currently efforts are underway to advance the back contact processing to the same level as outlined in the SOW. Preliminary results on interconnection have yielded very promising results. Mathematical modeling of a package design has yielded results that show that moisture can be kept from our device for 22 years at 65C temperature with saturated humidity. Hardware to perform steady state photocapacitance (PHCAP) has been designed, built and tested in our laboratory. The effect of processing on the deep states in CdTe devices can be seen quantitatively. Optimum process conditions lead to lower photocapacitance signals. Many devices and CdS/CdTe samples have been provided to many groups including Larry Olsen of PNNL. Based on our current progress, no difficulties are anticipated in successfully completing the future targets outlined in the SOW. In addition to the tasks outlined above, two members of our team attended the 31st IEEE PVSC. Two oral presentations (preprints were sent to you earlier) were given. In addition, a poster was presented at the ICTMC conference and this paper has been accepted for publication in a journal. A loadlock system for the 16" X 16" substrates has been designed and constructed and is being tested. This activity is supported by another program from DOE-EERE and cost shared by NSC. Two scientists from GE Global Research were given a detailed tour of our facilities and a detailed presentation of our technology was made. |
|---|
| Venue | XXL-5-44205-02 to Colorado State University |
|---|
| Source | Colorado State University |
|---|
| Document Type | Quarterly Report (Word document) |
|---|
| Resource Date | 03/2028 |
|---|
|
| Post Date | 09/09/2008 |
|---|
| Title | CHARACTERIZATION AND ANALYSIS OF CIS AND CDTE CELLS |
|---|
| Link | (PDF 94 KB) Download Acrobat Reader. |
|---|
| Author | J. R. Sites |
|---|
| Description | Discusses (contac) barrier measurement technique, CdTe internal photoemission measurement, non-uniform CdTe barriers affecting "roll-over", CdTe cells with thin CdS layers, sheet resistance and fill factor issues, the effect of shunts on cell performance contour plots (correlations of Voc, Jsc, and FF with material parameters, and collaborative work. |
|---|
| Venue | Colorado State University, Fort Collins, CO, subcontract XXL-5-44205-03, quarterly report |
|---|
| Source | Colorado State University |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 06/02/2009 |
|---|
|
| Post Date | 02/24/2009 |
|---|
| Title | CHARACTERIZATION OF THE ELECTRONIC AND CHEMICAL STRUCTURE AT THIN FILM SOLAR CELL INTERFACES |
|---|
| Link | (PDF 110 KB) Download Acrobat Reader. |
|---|
| Author | C. Heske |
|---|
| Description | We have initiated a detailed study of the CdS/CIGSe interface formation for world-record-class samples. A substantial data set has been recorded, and additional data-taking is currently ongoing. A series of XPS survey spectra is shown that were taken as a function of CdS thickness. Corresponding completed solar cell devices yielded efficiencies in the 15% range, while we are currently also investigating a sample series with efficiencies around 18%. These spectra, to-gether with detail spectra of each core level, the valence band maxima, and the work function are cur-rently being analyzed to develop a comprehensive picture of the electronic structure of these two CdS/CIGSe interface systems. |
|---|
| Venue | Subcontract XXL-5-44205-12 with U. Nevada, Las Vegas, quarterly report |
|---|
| Source | University of Nevada, Las Vegas |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 01/15/2009 |
|---|
|
| Post Date | 03/11/2009 |
|---|
| Title | FABRICATION AND PHYSICS OF CDTE DEVICES BY SPUTTERING |
|---|
| Link | (PDF 471 KB) Download Acrobat Reader. |
|---|
| Authors | A. Compaan, R. W. Collins, V. G. Karpov, D. Giolando |
|---|
| Description | RTSE has been applied to investigate the dielectric functions of CdTe and CdS thin films sputtered at different temperatures. These dielectric functions are modeled using the critical point (CP) parabolic band approximation. Key characteristics can be deduced including grain size, excitation group speeds, stress, and temperature from the CP parameters. Capabilities for on-line optical monitoring are sought to provide information, not only on layer thicknesses and compositions, but also on grain size, stress, and temperature. As a first application, the parameterization was used to analyze the ellipsometric spectra of a stepwise etched CdTe solar cell. In this study, depth profiles in the void and grain size near the CdTe/CdS interface have been obtained. |
|---|
| Venue | university of Toledo, subcontract ZXL-5-44205-01, quarterly report |
|---|
| Source | University of Toledo |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 11/19/2008 |
|---|
|
| Post Date | 11/21/2008 |
|---|
| Title | CHARACTERIZATION OF THE ELECTRONIC AND CHEMICAL STRUCTURE AT THIN FILM SOLAR CELL INTERFACES |
|---|
| Link | (PDF 107 KB) Download Acrobat Reader. |
|---|
| Author | C. Heske |
|---|
| Description | This project is devoted to deriving the electronic structure of interfaces in Cu(In,Ga)(S,Se)2 and CdTe thin film solar cells. By using a unique combination of spectroscopic methods (photoelectron spectroscopy, inverse photoemission, and X-ray absorption and emission) a comprehensive picture of the electronic (i.e., band alignment in the valence and conduction band) as well as chemical structure is painted.
In February this year, the NREL group announced to have achieved a new world record effi-ciency (19.9%) for Cu(In,Ga)Se2 ?CIGSe? ? based thin-film solar cells (Ingrid Repins, Miguel A. Con-treras, Brian Egaas, Clay DeHart, John Scharf, Craig L. Perkins, Bobby To and Rommel Noufi, 19.9%-efficient ZnO/CdS/CuInGaSe2 Solar Cell with 81.2% Fill Factor, Prog. Photovolt. 16, 235 (2008).) This recent efficiency gain (compared to the former world record - 19.5%), is believed to be caused by a small ? but apparently significant ? change in the three-stage process. In comparison to the deposition process used earlier, the difference resulting in the recent world record CIGSe absorber was a termina-tion of the third (and thus last) stage without Ga and hence is considered to be ?In-terminated?.
In order to shed light on the expected different chemical surface structure, we investigated a sample from the world record absorber batch (M2992) by x-ray photoelectron spectroscopy (XPS) and xray excited Auger electron spectroscopy (XAES). Both techniques are very surface sensitive (information depth a few nm) and thus well suited to address questions of surface termination. In addition, we also characterized a CIGSe absorber (M2995) deliberately terminated with Ga for comparison.
|
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| Venue | University of Nevada, Las Vegas, subcontract XXL-5-44205-12, quarterly report |
|---|
| Source | University of Nevada, Las Vegas |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 09/15/2008 |
|---|
|
| Post Date | 11/04/2008 |
|---|
| Title | PROCESSING, MATERIALS, DEVICES AND DIAGNOSTICS FOR THIN FILM PHOTOVOLTAICS: FUNDAMENTAL AND MANUFACTURING ISSUES |
|---|
| Link | (PDF 365 KB) Download Acrobat Reader. |
|---|
| Author | R. W. Birkmire |
|---|
| Description |
The Effort was focused on two sub-tasks: (1) fabrication of devices with thin CdTe absorber layers, and (2) development of mechanically flexible CdTe cells by deposition onto a temporary support followed by transfer to a flexible polymer substrate.
|
Best-cell J-V results for VT cells with thin CdTe absorber layers using vapor CdCl 2 treatment at 480ºC with 2 minute CdCl2
?m) |
V OC
(mV) |
J SC
(mA/cm 2) |
FF
(%) |
?
(%) |
|
3.0 |
788 |
23.1 |
64.0 |
11.8 |
|
1.5 |
807 |
23.8 |
56.8 |
10.9 |
|
1.0 |
743 |
23.4 |
54.8 |
9.5 |
|
0.8 |
723 |
22.5 |
50.5 |
8.2 |
|
|---|
| Venue | Institute of Energy Conversion, University of Delaware, subcontract ADJ-30630-12, monthly report |
|---|
| Source | University of Delaware |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 08/27/2008 |
|---|
|
| Post Date | 11/04/2008 |
|---|
| Title | PROCESSING, MATERIALS, DEVICES AND DIAGNOSTICS FOR THIN FILM PHOTOVOLTAICS: FUNDAMENTAL AND MANUFACTURABILITY ISSUES |
|---|
| Link | (PDF 439 KB) Download Acrobat Reader. |
|---|
| Author | R. W. Birkmire |
|---|
| Description | The report highlights progress for CdTe-based solar cells. During this period, effort was focused on two sub-tasks: (1) deposition and characterization of device structures with thin CdTe absorber layers and (2) deposition of CdTe/CdS/ITO onto a temporary supporting superstrate for transfer to a flexible polymer substrate. |
|---|
| Venue | Instutute of Energy Conversion, University of Delaware, subcontract ADJ-1-30630-12, monthly report |
|---|
| Source | University of Delaware |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 08/08/2008 |
|---|
|
| Post Date | 11/19/2008 |
|---|
| Title | FABRICATION AND PHYSICS OF CDTE DEVICES BY SPUTTERING |
|---|
| Link | (PDF 1.1 MB) Download Acrobat Reader. |
|---|
| Authors | A. Compaan, R. W. Collins, V. G. Karpov, D. Giolando |
|---|
| Description |
This report presents: 1) properties of phosphorus-doped CdTe films prepared by sputtering from pressed targets of CdTe and Cd3P2, 2) optimization studies on ultra-thin CdS/CdTe cells with efficiencies exceeding 10% for 0.5? |
|---|
| Venue | University of Toledo, subcontract ZXL-5-44205-01, (CdTe), quarterly report |
|---|
| Source | University of Toledo |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 08/2008 |
|---|
|
| Post Date | 07/09/2008 |
|---|
| Title | CHARACTERIZATION AND ANALYSIS OF CIS AND CDTE CELLS" |
|---|
| Link | (PDF 123 KB) Download Acrobat Reader. |
|---|
| Author | J. R. Sites |
|---|
| Description | We continued our work on the relationship between voltage and CdS thickness with CdTe cells; the relationship between fill-factor of a cell or module and sheet resistance, geometry, current, and the JSC/VOC ratio; and the effects of local shunts on cell performance. Since the funding of the AVA incubator project took effect, I have shifted our work on CSU and AVA CdTe cells, and the reporting of those results, to the incubator project.
|
|---|
| Venue | Coloradio State University, Subcontract XXL-5-44205-03, quarterly report |
|---|
| Source | Colorado State University |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 03/21/2008 |
|---|
|
| Post Date | 04/23/2008 |
|---|
| Title | FABRICATION AND PHYSICS OF CDTE DEVICES BY SPUTTERING |
|---|
| Link | (PDF 466 KB) Download Acrobat Reader. |
|---|
| Authors | A. Compaan, R. W. Collins, V. G. Karpov, D. Giolando |
|---|
| Description | We have observed that routine maintenance procedures such as CdTe target replacement and cleaning of the corresponding ground shield influence the deposition rate and the quality of the film. For example it has been found that the pinhole density reaches its maximum right after the cleaning of the ground shield and remains relatively high for a few subsequent depositions. On the other hand once a coating of CdTe is developed on the ground shield the pinhole density becomes vanishingly small although the deposition rate can slow by as much as 50% as the ground shroud coating builds up.
Not only does this present difficulties for maintaining a solid efficiency baseline throughout the sputtering target life cycle, it also reflects changes in the sputtering plasma. Being a plasma-assisted deposition technique, magnetron sputtering offers a wide range of tweaking opportunities to create thin films with desired physical properties. Without good understanding of the plasma processes the sputtering process can become excessively complicated.
The basic principles of magnetron sputtering are well known and readily available in the literature. It is important to apply those principles to a specific deposition process and equipment. In this report we provide the results of the potential distribution measurements done in one of the CdTe deposition chambers at the University of Toledo. This is the same chamber we recently reported the study of the deposition rate and the CdTe film morphology. These measurements of the plasma allow us to link the typical process control data from pressure gauges and power meters to the properties of the deposited film to potential distributions inside the chamber and plasma parameters extracted from the Langmuir probe measurements. |
|---|
| Venue | University of Toledo (CdTe), subcontract ZXL-5-44205-01, quarterly report |
|---|
| Source | University of Toledo |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 03/2008 |
|---|
|
| Post Date | 04/23/2008 |
|---|
| Title | FABRICATION AND PHYSICS OF CDTE DEVICES BY SPUTTERING |
|---|
| Link | (PDF 744 KB) Download Acrobat Reader. |
|---|
| Authors | A. Compaan, R. W. Collins, V. G. Karpov, D. Giolando |
|---|
| Description | We have developed a theory of ac response by systems of distributed diodes in parallel with resistors and capacitors connected through resistive electrodes that can represent many practical devices including photovoltaics and Schottky junctions. In particular, we have shown that:
1. There exist three lateral decay lengths related to the system diodes, shunt resistors, and capacitances respectively that determine the effective frequency-dependent lateral decay length L and describe the physics of ac response in such distributed systems;
2. The response is frequency-independent below a certain characteristic frequency, above which it strongly depends on testing frequency;
3. The 1D and 2D systems behave similarly in the large device regime, l >> L, where l is the device lateral dimension, while in the small device regime, l << L, 2D systems exhibit certain unique behavior;
4. Both the capacitance and conductance are described by closed form analytical expressions as functions of frequency and dc bias and are parametrically dependent on system material characteristics;
5. Our theoretical results establish a basis for a type of admittance characterization applicable to a wide variety of semiconductor structures including photovoltaics and Schottky junctions. |
|---|
| Venue | University of Toledo (CdTe), subcontract ZXL-5-44205-01, quarterly report |
|---|
| Source | University of Toledo |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 03/2008 |
|---|
|
| Post Date | 12/13/2007 |
|---|
| Title | BARRIER COATINGS AND STABILITY OF THIN FILM SOLAR CELLS |
|---|
| Link | (PDF 51 KB) Download Acrobat Reader. |
|---|
| Author | L. Olsen |
|---|
| Description | Data were acquired for SSI mini-modules that were coated with PNNL barrier coatings based on the new polymer blend. Results were obtained for coated modules subjected to 85ºC and dry conditions, and modules with barrier coatings of thicknesses ranging from 3 microns to 10 microns. The 85ºC/Dry testing was done to determine if the coatings react in a negative way with the devices. We found that all coated modules were stable in the 85ºC/Dry conditions. Figure 3 gives results for a module with a coating 10 microns thick. Basically, the module is stable. Thus, it is very clear that the SSI mini-module can tolerate 85ºC and dry conditions, but not a stress of 86ºC/85%RH.
Figure 4 gives results for coated mini-modules with the results for a bare module shown for contrast. Although the PNNL barrier coatings have made a tremendous difference, degradation still occurs. The fact that all modules degrade at the same rate, regardless of coating thickness, provides an important clue as to the cause of the degradation. Based on our overall experience, the effectiveness of the barrier coatings should improve with thickness. In general, we find that there are three cell features that can lead to defects in the multi-layer coatings which in turn provide a path for water diffusion:
(i) Surface roughness;
(ii ) Inadequate edge seal;
(iii) Cuts separating individual cells.
Since the rate of degradation of efficiency is independent of the coating thickness, we suspect that features (ii) and (iii) are most likely responsible for causing pathways of moisture diffusion. Further studies are required before this problem(s) can be clearly identified. However, the results achieved with the new polymer blends in an 85/85 environment are very encouraging. |
|---|
| Venue | Pacific Northwest National Laboratory, subcontract DAX-4-44239-01, quarterly report |
|---|
| Source | Pacific Northwest National Lab (PNNL) |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 12/01/2007 |
|---|
|
| Post Date | 02/07/2008 |
|---|
| Title | CHARACTERIZATION OF THE ELECTRONIC AND CHEMICAL STRUCTURE AT THIN FILM SOLAR CELL INTERFACES |
|---|
| Link | (PDF 122 KB) Download Acrobat Reader. |
|---|
| Author | C. Heske |
|---|
| Description | We have derived the electronic structure of the CdS/CIGSe interface in thin film solar cells prepared by NREL. The conduction band alignment at the CdS/CIGSe interface is flat, as expected for a high efficiency CIGSe solar cell. Furthermore, we find direct evidence for a strong interface dipole. Together with the previously reported lack of significant intermixing at the CdS/CIGSe interface, we thus find a modified electronic and chemical interface structure compared to previously studied (less efficient) devices from other manufacturers. |
|---|
| Venue | University of Nevada, Las Vegas, subcontract XXL-5-44202-12, quarterly report |
|---|
| Source | University of Nevada, Las Vegas |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 11/15/2007 |
|---|
|
| Post Date | 11/13/2007 |
|---|
| Title | FABRICATION AND PHYSICS OF CDTE DEVICES BY SPUTTERING |
|---|
| Link | (PDF 495 KB) Download Acrobat Reader. |
|---|
| Authors | A. Compaan, R. W. Collins, V. G. Karpov |
|---|
| Description | The focus of research during this quarter was on back contact development and on the advanced analysis of CdS using real time spectroscopic ellipsometry and its potential applications for monitoring of production lines for CdTe solar cell fabrication.
A dielectric function parameterization is possible that uses the grain size as a controlling parameter -- similar to what is now possible with void fraction. |
|---|
| Venue | U. Toledo, subcontract ZXL-5-44205-01, quarterly report |
|---|
| Source | University of Toledo |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 11/05/2007 |
|---|
|
| Post Date | 11/13/2007 |
|---|
| Title | FABRICATION AND PHYSICS OF CDTE DEVICES BY SPUTTERING |
|---|
| Link | (PDF 447 KB) Download Acrobat Reader. |
|---|
| Authors | A. Compaan, R. W. Collins, V. G. Karpov |
|---|
| Description | We describe a series of experiments involving peel-off of the back contact and then recontacting again while several measurements were made along the way with x-ray fluorescence to monitor the Cu signal and other measurements were made with high resolution SEM and TEM. Finally, x-ray fine structure measurements provide information on the bonding of Cu in the finished cells. All three measurements together provide evidence that Cu remains localized predominantly very near the back contact in the UT sputtered cells with evaporated Cu/Au back contacts. |
|---|
| Venue | University of Toledo, subcontract ZXL-5-44205-01, quarterly report |
|---|
| Source | University of Toledo |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 11/05/2007 |
|---|
|
| Post Date | 01/14/2008 |
|---|
| Title | PROCESSING, MATERIALS, DEVICES AND DIAGNOSTICS FOR THIN FILM PHOTOVOLTAICS: FUNDAMENTAL AND MANUFACTURABILITY ISSUES |
|---|
| Link | (PDF 258 KB) Download Acrobat Reader. |
|---|
| Author | R. W. Birkmire |
|---|
| Description | The IEC VT deposition process is being used to deposit CdTe films with thickness approaching 1 micron suitable for cells with 11% conversion efficiency. However, the thickness uniformity of the obtained deposit is more difficult to control in the high deposition rate regime (10 mm/min) than for baseline thickness ~5-7 mm. Also, the films are more prone to having voids in the CdTe layer, which become shunt paths in devices. The post-deposition processing becomes more critical since thinner films have smaller grains and are therefore more sensitive to grain boundary-enhanced processes such as interdiffusion of CdS-CdTe, oxide penetration, and penetration from any etchants used to process the back contact. In the previous year of work, we showed that 11% baseline performance could be maintained with 1.5-3 micron thick CdTe by reducing the CdCl2 vapor treatment processing time, using milder etchants, and reducing the Cu quantity at the back contact, either by depositing a thinner layer or by incorporating the Cu into the ZnTe contact. |
|---|
| Venue | Institute of Energy Conversion, University of Delaware, subcontrat ADJ-1-30630-12, monthly report |
|---|
| Source | University of Delaware |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 10/25/2007 |
|---|
|
| Post Date | 11/29/2007 |
|---|
| Title | CHARACTERIZATION AND ANALYSIS OF CIS AND CDTE CELLS |
|---|
| Link | (PDF 70 KB) Download Acrobat Reader. |
|---|
| Author | J. R. Sites |
|---|
| Description | During the past quarter, two students completed their PhD and one other is preparing for his defense. At the same time, we expanded our work on the analysis of cells with non-uniformities, we began a collaboration on CIGS made with laser-assisted deposition, and we continued several measurement and analysis projects in collaboration with other laboratories. |
|---|
| Venue | Colorado State University, subcontract XXL-5-44205-03, quarterly report |
|---|
| Source | Colorado State University |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 09/24/2007 |
|---|
|
| Post Date | 11/21/2007 |
|---|
| Title | PROCESSING, MATERIALS, DEVICES AND DIAGNOSTICS FOR THIN FILM PHOTOVOLTAICS: FUNDAMENTAL, AND MANUFACTURABILITY ISSUES |
|---|
| Link | (PDF 321 KB) Download Acrobat Reader. |
|---|
| Author | R. W. Birkmire |
|---|
| Description |
Issues related to high throughput processing of and junction- limiting factors in thin film CdTe solar cells are reported. Concerns over possible sources of impurity contamination of CdTe has prompted further analysis of the influence of soda lime glass (SLG) SLG/SnO2 substrate preparation as well as the chemistry of the CdS growth and its effect on the CdS-CdTe junction region. With respect to high throughput deposition and CdTe usage, we have deposited CdTe films by VT with sub-micron thickness having low pinhole density. |
|---|
| Venue | IEC, University of Delaware, subcontract ADJ-1-30630-12, monthly report |
|---|
| Source | University of Delaware |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 09/21/2007 |
|---|
|
| Post Date | 08/15/2007 |
|---|
| Title | BARRIER COATINGS AND STABILITY OF THIN FILM SOLAR CELLS |
|---|
| Link | (PDF 89 KB) Download Acrobat Reader. |
|---|
| Author | L. Olsen |
|---|
| Description | The key objectives of the program are to develop low cost barrier coatings for CIS and CdTe solar cells and to develop an improved understanding of the effects of water on the stability of these types of cells. The scope of this work entails investigations multilayer, barrier coatings for CIS and CdTe thin film solar cells, and studies of stability issues, particularly those related to moisture ingress. Investigation of barrier coatings on SSI and CSU devices will continue in an effort to establish effective approaches encapsulate CIS and CdTe modules. Studies will also be directed towards issues concerning cost of the coating process. The program will be structured into three major tasks: (1) Barrier coatings and stability studies for CIS Solar Cells; (2) Barrier coatings and stability studies for CdTe solar cells; (3) Low cost coating process development. |
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| Venue | PNNL, agreement DAX-4-44239-01, quarterly report |
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| Source | Pacific Northwest National Lab (PNNL) |
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| Document Type | Quarterly Report (Adobe Postscript file) |
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| Resource Date | 06/2007 |
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|
| Post Date | 08/03/2007 |
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| Title | CHARACTERIZATION AND ANALYSIS OF CIS AND CDTE CELLS |
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| Link | (PDF 66 KB) Download Acrobat Reader. |
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| Author | J. R. Sites |
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| Description | Reports CIGS nonuniformities, CdTe efficiency (n-p vs. p-i-n), light bias QE, and CdS thickness variation in CdTe cells (all presented at the MRS Spring meeting) |
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| Venue | Colorado State University (Sites), subcontract XXL-5-44205-03, quarterly report |
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| Source | Colorado State University |
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| Document Type | Quarterly Report (Adobe Postscript file) |
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| Resource Date | 05/27/2007 |
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|
| Post Date | 08/15/2007 |
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| Title | BARRIER COATINGS AND STABILITY OF THIN FILM SOLAR CELLS |
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| Link | (PDF 56 KB) Download Acrobat Reader. |
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| Author | L. Olsen |
|---|
| Description | Our investigations to date were based on Shell Solar, Inc. (SSI) cells and mini-modules. We found that these cells were extremely vulnerable to damp heat effects. These devices are no longer available to PNNL due to the closing of the Chatsworth CIGS operation. However, we have a supply of 2 in. x 2 in. mini-modules that were used in recent studies that are discussed in this report. Moisture ingress is apparently not an issue if modules are fabricated with glass-to-glass construction. It is clear, however, that CIGS cells and modules fabricated on flexible substrates must have an effective barrier coating. As a result, we plan to concentrate on establishing baseline information concerning the effects of damp heat on CIGS. |
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| Venue | PNNL, agreement DAX-4-44239-01, quarterly report |
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| Source | Pacific Northwest National Lab (PNNL) |
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| Document Type | Quarterly Report (Adobe Postscript file) |
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| Resource Date | 05/2007 |
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|
| Post Date | 06/25/2007 |
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| Title | PROCESSING, MATERIALS, DEVICES AND DIAGNOSTICS FOR THIN FILM PHOTOVOLTAICS: FUNDAMENTAL AND MANUFACTURING ISUES |
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| Link | (PDF 235 KB) Download Acrobat Reader. |
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| Author | R. W. Birkmire |
|---|
| Description | Issues related to high throughput processing of and junction- limiting factors in CdTe solar cells are reported. Based on the effects of TCO/substrate cleaning described in the previous report, we continued with the study of uncontrolled impurities originating in the glass/SnO 2 substrate. It is vital that this source of variability in film morphology and device performance is eliminated prior to development of cells with sub-micron absorber thickness and evaluation of approaches for VOC > 900 mV. In this report, we present the details of procedures used to establish a performance baseline with cell efficiency >11% for processing CdTe/CdS cells with vapor transport deposited CdTe onto moving commercially available substrates at high growth rate (~10 m/min) using rapid post-deposition processing, with less than 1 min per processing step. |
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| Venue | Institute of Energy Conversion, U. Delaware, Suibcontract ADJ-1-30630-12, monthly report |
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| Source | University of Delaware |
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| Document Type | Quarterly Report (Adobe Postscript file) |
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| Resource Date | 04/24/2007 |
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|
| Post Date | 03/14/2007 |
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| Title | PROCESSING, MATERIALS, DEVICES AND DIAGNOSTICS FOR THIN FILM PHOTOVOLTAICS: FUNDAMENTAL AND MANUFACTURABILITY ISSUES |
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| Link | (PDF 146 KB) Download Acrobat Reader. |
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| Author | R. W. Birkmire |
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| Description | A study is warranted to determine the effects of glass handling and cleaning and buffer layer formation on the grain structure and variability in performance of the CdTe devices. Statistical analysis of the device performance of more than 450 VT devices using the baseline process revealed a V OC distribution with a sharp maximum at 800 mV and excursions to 850 mV. The effort to demonstrably improve VOC and to fabricate cells with ultra-thin absorber layers will require a tighter baseline distribution. Due to the combination of superstrate configuration and high processing temperatures used for VT CdTe solar cells, uncontrolled impurities originating in the glass/SnO2 and its handling can become trapped in the structure and critically affect junction quality, in which case the intrinsic buffer layer may serve as a diffusion barrier as well as an electronic circuit element. The role of the Ga2O3 in mitigating effects from the SnO2 is demonstrated in for cells made from a single VT deposition with and without Ga2O3 and CdS in the window side of the device. |
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| Venue | IEC, University of Delaware, subcontract ADJ-1-30630-12, monthly report |
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| Source | N/A |
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| Document Type | Quarterly Report (Adobe Postscript file) |
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| Resource Date | 01/31/2007 |
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|
| Post Date | 02/15/2007 |
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| Title | CHARACTERIZATION OF THE ELECTRONIC AND CHEMICAL STRUCTURE AT THIN FILM SOLAR CELL INTERFACES |
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| Link | (PDF 348 KB) Download Acrobat Reader. |
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| Authors | M. Baer, C. Heske |
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| Description | This project is devoted to deriving the electronic structure of interfaces in Cu(In,Ga)(S,Se)2 and CdTe thin film solar cells. By using a unique combination of spectroscopic methods (photoelectron spectroscopy, inverse photoemission, and X-ray ab-sorption and emission) a comprehensive picture of the electronic (i.e., band alignment in the valence and conduction band) as well as chemical structure can be painted. The work focuses on (a) deriving the bench mark picture for world-record cells, (b) analyze state-of-the-art cells from industrial processes, and (c) aid in the troubleshooting of cells with substandard performance. In the last months, we started to investigate CdS/CIGSe samples provided by the National Renewable Energy Laboratory.
We do not find any evidence for a very strong intermixing process (i.e., S atoms diffusing into the substrate). However, the environment of the sulfur atoms at the growth start of the interface clearly deviates from a perfect CdS environment. Whether this is due to a less perfect crystalline structure (i.e., the formation of very small nm-scale nanoparticles) or some S diffusing into the CIGSe absorber can not unambiguously be differentiated. |
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| Venue | U. Nevada, Las Vegas, subcontract XXL-5-44205-12, quarterly report |
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| Source | University of Nevada, Las Vegas |
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| Document Type | Quarterly Report (Adobe Postscript file) |
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| Resource Date | 01/11/2007 |
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|
| Post Date | 03/14/2007 |
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| Title | BARRIER COATINGS AND STABILITY OF THIN FILM SOLAR CELLS |
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| Link | (PDF 47 KB) Download Acrobat Reader. |
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| Author | L. Olsen |
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| Description | Studies of photoluminescence in CdTe solar cell structures continued. The objective of this effort is to determine if the PL spectrum for a CdTe device is affected by stress. In particular, we are interested in determining if moisture affects carrier properties. Samples studied were cell structures without back contacts previously provided by CSU. Figure 1 describes our approach to PL studies. This figure is repeated from the last quarterly report. An excitation wavelength of 580 nm was used and band gap emission observed for the excitation beam entering through the glass and through the CdTe side. |
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| Venue | PNNL, DAX-4-44239-01, quarterly report |
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| Source | Pacific Northwest National Lab (PNNL) |
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| Document Type | Quarterly Report (Adobe Postscript file) |
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| Resource Date | 01/2007 |
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|
| Post Date | 01/30/2007 |
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| Title | FABRICATION AND PHYSICS OF CDTE DEVICES BY SPUTTERING |
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| Link | (PDF 1.0 MB) Download Acrobat Reader. |
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| Authors | A. Compaan, R. W. Collins, V. G. Karpov |
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| Description | This progress report covers the First Quarter of Phase 2 for the period from June 1, 2006 through August 31, 2006, of the above Thin Film Photovoltaic Partnership Program subcontract. The focus of research during this quarter was on materials issues including high rate deposition and in situ real time analysis of film growth and post-processing. Results of high rate sputter deposition (Task 2.1.3) and real-time spectroscopic ellipsometry study of rf-sputtered solar cells (task 2.3.3) have been described. The most important data obtained from this study are the optical properties of the alloys as functions of composition as well as measurement temperature. |
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| Venue | University of Toledo (CdTe), subcontract ZXL-5-44205-01, Quarterly Report |
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| Source | University of Toledo |
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| Document Type | Quarterly Report (Adobe Postscript file) |
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| Resource Date | 12/2006 |
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|
| Post Date | 01/08/2007 |
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| Title | CHARACTERIZATION AND ANALYSIS OF CIS AND CDTE CELLS |
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| Link | (PDF 106 KB) Download Acrobat Reader. |
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| Author | J. R. Sites |
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| Description | Alan Davies has been working closely with Sampath?s group, Al Enzenroth in particular, to explore buffer layers that would allow the CSU cells to be made with thinner CdS without compromising performance in other ways. Alan Fahrenbruch, also using CdTe cells fabricated by Sampath?s group, has examined transient effects related to photoconductivity and has related these to anomalous AQE effects.
Ana Kanevce has added nonuniformities in diode voltage to her simulations of CIGS cells with submicron absorber layers. Several physical conditions (reduced local Ga concentration, reduced local thickness, reduced back electron reflector) can be well approximated by a weak diode with a lower value of VOC in the midst of an array of normal diodes.
Ana also worked with Raghu Bhattacharya of NREL on the analysis of CIGS cells that that were fabricated with a solution-grown CdZnS buffer layer. The best of these cells achieved 19.5% efficiency, equal to that achieved with NREL?s standard CdS buffer. At short wavelengths, the CdZnS buffer did achieve about 2 mA/cm2 higher current than the CdS buffer, but it also had slightly less collection in the longer wavelength region. |
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| Venue | Colorado State University, subcontract XXL-5-44205-03, quarterly report |
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| Source | Colorado State University |
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| Document Type | Quarterly Report (Adobe Postscript file) |
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| Resource Date | 11/27/2006 |
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|
| Post Date | 12/22/2006 |
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| Title | BARRIER COATINGS AND STABILITY OF THIN FILM SOLAR CELLS |
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| Link | (PDF 106 KB) Download Acrobat Reader. |
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| Author | L. Olsen |
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| Description | No substrates with CdTe cell structures were received this quarter from CSU or UT. As a result, studies of photoluminescence in CdTe solar cell structures were initiated. The objective of this effort is to determine if the PL spectrum for a CdTe device is affected by stress. In particular, we are interested in determining if moisture affects carrier properties. Samples studied were cell structures without back contacts provided a year ago by CSU. The approach to the PL studies is described in Figure 1. An excitation wavelength of 580 nm was used and band gap emission observed for the excitation beam entering the through the glass and through the CdTe side. |
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| Venue | PNNL, Memorandum Purchase Order ("subcontract") DAX-4-44239-01, quarterly report |
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| Source | Pacific Northwest National Lab (PNNL) |
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| Document Type | Quarterly Report (Adobe Postscript file) |
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| Resource Date | 11/2006 |
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|
| Post Date | 12/20/2006 |
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| Title | MANUFACTURING PROCESS OPTIMIZATION TO IMPROVE STABILITY, YIELD, AND EFFICIENCY OF CDS/CDTE PV DEVICES |
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| Link | (PDF 98 KB) Download Acrobat Reader. |
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| Author | W. S. Sampath |
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| Description | We have progressed on the tasks outlined in our SOW for Phase II. Significant advances to the design of module packaging have been made. Desiccant containing materials for the edge seal and sealing of the holes in the back glass have been tested in damp heat tests at NREL with very promising results. Hardware modifications to the pilot system for automated cooling of the substrate in vacuum have been completed and device efficiencies of 11.83 % have been made in "all forward" process. Significant progress has been made in characterizing films with ellipsometry and the use of ellipsometry for quality control is being investigated. Efforts to improve device efficiency and advance device characterization are underway. Based on our current progress, no difficulties are anticipated in successfully completing the future targets outlined in the SOW. A prototype production system to process 16.5x16.5 inch substrates continues to be advanced. This activity is supported by another program from DOE-EERE and cost shared by National Starch and Chemicals (NSC). |
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| Venue | Colorado Stae University, subcontract XXL-5-44205-02, quarterly report |
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| Source | Colorado State University |
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| Document Type | Quarterly Report (Adobe Postscript file) |
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| Resource Date | 10/17/2006 |
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|
| Post Date | 12/08/2006 |
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| Title | CHARACTERIZATION OF THE ELECTRONIC AND CHEMICAL STRUCTURE AT THIN FILM SOLAR CELL INTERFACES |
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| Link | (PDF 199 KB) Download Acrobat Reader. |
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| Author | C. Heske |
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| Description | This project is devoted to deriving the electronic structure of interfaces in Cu(In,Ga)(S,Se)2 and CdTe thin film solar cells. By using a unique combination of spec-troscopic methods (photoelectron spectroscopy, inverse photoemission, and X-ray ab-sorption and emission) a comprehensive picture of the electronic (i.e., band alignment in the valence and conduction band) as well as chemical structure can be painted. The work focuses on (a) deriving the bench mark picture for world-record cells, (b) analyze state-of-the-art cells from industrial processes, and (c) aid in the troubleshooting of cells with substandard performance.
We could gather first results for Cu(In,Ga)Se2 (?CIGSe?) and Cu(In,Ga)(S,Se2) (?CIGSSe?) samples prepared by the group of W. Shafarman (Institute of Energy Conversion, University of Delaware). The aim of the conducted experiments is to shed light on the deeply buried absorber/back contact interface in terms of its chemical and electronic properties. We had to develop a suitable lift-off (or cleavage) technique, which allowed us to cleave the absorber/Mo/glass samples at the desired interface. It turned out that gluing the front side of the absorber/Mo/glass thin film stack to a stainless a steel plate using a conductive (Ag-containing) epoxy allows a subsequent division of the stack in two parts and provides the necessary conductivity for the PES measurements. In all cases the thin film stack cleaved at the absorber/Mo inter-face. However, there were differences in terms of the area exposed after lift-off. Compar-ing the CIGSe/Mo/glass and CIGSSe/Mo/glass samples with respect to their cleavage behavior, it seems that for the latter it is rather easy to lift off large areas (in the range of cm2). This is favorable with respect to the characterization by PES but even more impor-tant for the planned inverse photoemission (IPES) measurements, since the IPES detector is not able to ?artificially? reduce the spot size of the e-gun on the sample (which is approx. 1 cm^2) as it can easily be done in the PES case, probing differently sized areas by using different lens modes of the electron analyzer. |
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| Venue | U. Nevada, Las Vegas, Subcontract No. XXL-5-44205-12, quarterly report |
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| Source | University of Nevada, Las Vegas |
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| Document Type | Quarterly Report (Adobe Postscript file) |
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| Resource Date | 10/15/2006 |
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|
| Post Date | 11/07/2006 |
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| Title | PROCESSING, MATERIALS, DEVICES AND DIAGNOSTICS FOR THIN FILM PHOTOVOLTAICS: FUNDAMENTAL AND MANUFACTURABILITY ISSUES |
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| Link | (PDF 1.9 MB) Download Acrobat Reader. |
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| Author | R. W. Birkmire |
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| Description | During this reporting period, effort continued on high throughput fabrication of thin film CdTe/CdS cells with CdTe deposited by vapor transport (VT). The CdS films were deposited by chemical surface deposition (CSD) onto 10 x 10 cm plates of Pilkington TEC15 SnO 2/glass. Particular focus was placed on Ga deposition for the high resistance (HR) Ga2O3 buffer layer and on the chemical state of the TCO. Analysis of the chemical state of the CdTe surface after aniline treatment continued and shows that, like other etchants, the aniline treatment removes surface-bound oxygen and chlorine, generates Te, but also may leave a trace hydrocarbon residue behind. |
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| Venue | IEC (U. Delaware), subcontract ADJ-1-30630-12, quarterly report |
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| Source | University of Delaware |
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| Document Type | Quarterly Report (Adobe Postscript file) |
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| Resource Date | 10/04/2006 |
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|
| Post Date | 09/28/2006 |
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| Title | BARRIER COATINGS AND STABILITY OF THIN FILM SOLAR CELLS |
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| Link | (PDF 42 KB) Download Acrobat Reader. |
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| Author | L. Olsen |
|---|
| Description | Efforts have concentrated on establishing procedures for collaboration with Dr. Sampath's group at CSU and Dr. Compaan's group at the University of Toledo. In both cases, we have supplied patterned SnO2 - coated glass for growth of CdS/CdTe structures. It turns out, however, that removing SnO2 from LOF TEC 15 is not trivial. We received valuable guidance from Dr. Sampath. Referring to Figure 1, we plan to start with SnO2 -coated glass, pattern the SnO2 as illustrated in Figure 1A, send the substrates to CSU and UT for growth of CdS/CdTe devices. In the case of CSU, the back contact will be applied at PNNL for some of the structures. Removing the tin-oxide has turned out to be non-trivial. |
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| Venue | PNNL, Purchase Order DAX-4-44239-01, quarterly report |
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| Source | Pacific Northwest National Lab (PNNL) |
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| Document Type | Quarterly Report (Adobe Postscript file) |
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| Resource Date | 08/2006 |
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|
| Post Date | 09/19/2006 |
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| Title | PROCESSING, MATERIALS, DEVICES AND DIAGNOSTICS FOR THIN FILM PHOTOVOLTAICS: FUNDAMENTAL AND MANUFACTURABILITY ISSUES |
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| Link | (PDF 173 KB) Download Acrobat Reader. |
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| Author | R. W. Birkmire |
|---|
| Description | CdTe cell fabrication focused on evaluation of alternative high resistance (HR) buffer layers and the influence of ambient composition during vapor transport (VT) CdTe deposition and vapor CdCl2 treatment. Aspects of CdTe surface chemistry were investigated with respect to rapid vapor CdCl2 treatment and anilinine etching. Bifacial solar cell analysis of cells with different CdTe thickness was carried out to provide detailed understanding of device operation and its relation to processing optimization. |
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| Venue | IEC, U. of Delaware, subcontract ADJ-1-30630-12, monthly report |
|---|
| Source | University of Delaware |
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| Document Type | Quarterly Report (Adobe Postscript file) |
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| Resource Date | 07/31/2006 |
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|
| Post Date | 07/25/2006 |
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| Title | BARRIER COATINGS |
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| Link | (MS Word 145 KB) |
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| Author | L. Olsen |
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| Description | Coatings to protect thin film cells. |
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| Venue | Quarterly Phase 2, #2 |
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| Source | Pacific Northwest National Lab (PNNL) |
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| Document Type | Quarterly Report (Word document) |
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| Resource Date | 07/2006 |
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|
| Post Date | 07/13/2006 |
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| Title | CHARACTERIZATION AND ANALYSIS OF CIS AND CDTE CELLS |
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| Link | (MS Word 42 KB) |
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| Author | J. R. Sites |
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| Description | During the past quarter, our group made progress in several areas as outlined below. Several of us participated actively in the CdTe and CIS team meetings. I made a trip to IEC in February to give a colloquium and discussion several topics of mutual interest. Adjacent to that visit, I attended to the DOE PV module-reliability meeting in Baltimore. I also participated (not at NREL expense) in the DOE?s SAI-input meeting that took place in Chicago in March. Our primarily work with industrial partners was LBIC measurements on Nanosolar cells and with assistance to Heliovolt in the design of current-voltage and quantum-efficiency measurement systems for their cells. |
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| Venue | Quarterly Report V (February - April 2006) Subcontract XXL-5-44205-03 For additional information: www.physics.colostate.edu/groups/photovoltaic |
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| Source | Colorado State University |
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| Document Type | Quarterly Report (Word document) |
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| Resource Date | 07/2006 |
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|
| Post Date | 05/30/2006 |
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| Title | INNOVATIVE CHARACTERIZATION OF AMORPHOUS AND THIN-FILM SILICON FOR IMPROVED MODULE PERFORMANCE |
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| Link | (PDF 416 KB) Download Acrobat Reader. |
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| Author | J. D. Cohen |
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| Description | Although nc-Si:H does not suffer as severely from light exposure as amorphous silicon, prolonged light soaking typically reduces the conversion efficiency by several percent . Several of our samples were examined both in ?State A?, after a sample had been annealed for 1 hour at 450 K, as well as in ?State B?, a degraded state which we obtained by exposing the sample to 20 hours of red-filtered light (>620 nm) from a tungsten-halogen source at an intensity of 400 mW/cm 2. Effects of such light soaking could be observed both in the photo-transient spectra as well as in drive-level capacitance profiles (DLCP). We see that the TPC signal changes significantly. In particular, the negative signals near 1.5 eV become significantly positive in State B. This corresponds to a loss of hole collection, even more than was achieved by reducing the measurement temperature from 295 K to 275 K in State A. What is particularly surprising, however, is that when such a deep defect response is apparent, we consistently have found that it decreased after prolonged light exposure. |
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| Venue | University of Oregon, 3rd Quarterly report, Subcontract ZXL-5-44205-11 |
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| Source | University of Oregon |
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| Document Type | Quarterly Report (Adobe Postscript file) |
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| Resource Date | 05/30/2006 |
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|
| Post Date | 05/02/2006 |
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| Title | STUDIES OF BASIC ELECTRONIC PROPERTIES OF CDTE-BASED SOLAR CELLS |
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| Link | (PDF 22 KB) Download Acrobat Reader. |
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| Author | J. Beach |
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| Description | Study of Deep Electronic States controlling VOC. |
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| Venue | CSM Extension of ADJ-2-30630-05, |
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| Source | Colorado School of Mines, Golden, CO |
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| Document Type | Quarterly Report (Adobe Postscript file) |
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| Resource Date | 05/01/2006 |
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|
| Post Date | 05/30/2006 |
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| Title | BARRIER COATINGS AND STABILITY OF THIN FILM SOLAR CELLS |
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| Link | (MS Word 87 KB) |
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| Author | L. Olsen |
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| Description | CdTe cell structures provided by CSU were stressed and then characterized with XPS in an effort to understand the effects of moisture on CdTe devices. If we assume the emission is primarily due to oxides on the grain boundaries, it appears that the unknown complex oxide could play a key role in grain boundary passivation. It could therefore be very valuable to determine the identity of this complex oxide. Based on results for the stressed cell, significant effects of the 60ºC/90%RH stress may be formation of Cd(OH)2 along grain boundaries, and elimination of the unknown complex Cd-based oxide along the grain boundaries. If we assume that the unknown oxide is important for grain boundary passivation and/or the hydroxide results in increased recombination at grain boundaries, then it is understandable that both Jsc and Voc would decrease as a result of damp heat. We conclude, therefore, that damp heat does more than just degrade the contacts in CdTe cells. In particular, it appears that formation of Cd(OH)2 leads to increased recombination at grain boundaries, which decreases cell quantum efficiency and increases current losses (larger Jo). |
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| Venue | 1st Quarterly Report - Phase II: September 1, 2005 -- November 30, 2005 NREL Subcontract: 48027 |
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| Source | Pacific Northwest National Lab (PNNL) |
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| Document Type | Quarterly Report (Word document) |
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| Resource Date | 05/2006 |
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|
| Post Date | 06/12/2006 |
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| Title | CHARACTERIZATION OF THE ELECTRONIC AND CHEMICAL STRUCTURE AT THIN FILM SOLAR CELL INTERFACES |
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| Link | (PDF 78 KB) Download Acrobat Reader. |
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| Authors | M. Baer, C. Heske |
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| Description | Eight CdTe materials samples used in actual solar cell were investigated by X-ray emission spectroscopy (XES). This technique provides detailed informations about the chemical properties of the investigated samples. XES as a photon-in photon-out technique probes the ?near-surface? bulk. In our case, where we have focused on the S L2,3 and Cl L2,3 emission, this method has an information depth of about 100 nm.
Based on the results obtained, we will continue the investigation of CdTe/CdS samples and extend them by investigating customized sample series with UPS and IPES to get insight into the band alignments at the various interfaces of the device structure of an CdTe-based solar cell. At the recent CdTe R&D team meeting (as well as at the CIS R&D team meeting) we have initiated a sample exchange with several (six) groups from within the Thin Film Photovoltaic Partnership Program. The planned experiments will shed light on the various interfaces in both CIS and CdTe cells. First samples have already been received at UNLV. |
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| Venue | Subcontract XXL-5-44205-12, University Nevada, Las Vegas, quarterly report |
|---|
| Source | University of Nevada, Las Vegas |
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| Document Type | Quarterly Report (Adobe Postscript file) |
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| Resource Date | 04/15/2006 |
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|
| Post Date | 04/19/2006 |
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| Title | CDTE |
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| Link | (PDF 160 KB) Download Acrobat Reader. |
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| Author | B. E. McCandless |
|---|
| Description | Summary: The CdTe cell fabrication effort focused on CdTe deposition and post deposition processing to increase throughput and raise baseline cell efficiency. The effect of carrier gas composition and substrate temperature on vapor transport (VT) CdTe film growth and device performance was evaluated. Vapor CdCl2 treatments, which
allow the treatment temperature to be separated from the CdCl2 and O2 concentration, were refined to allow a new baseline process to be defined with treatments ~ 2 minute in duration. Reduction in treatment time required increasing the treatment temperature of the CdTe/CdS and maintaining the partial pressures of CdCl2 and O2 to ~5 mTorr and
120 Torr, respectively. Similarly, the aniline photo-activated surface treatment was refined to permit effective Te formation in less than 5 minutes, by increasing the intensity of the incident light. In the area of device performance, analysis of J(V) curves has indicated that most CdTe cells can be described with three circuit elements: by a single
forward diode (given by A, Jo), a resistance (R), and a voltage dependent photocurrent. |
|---|
| Venue | ADJ-1-30630-12 |
|---|
| Source | University of Delaware |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 04/2006 |
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|
| Post Date | 04/27/2006 |
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| Title | CSU CDTE |
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| Link | (MS Word 58 KB) |
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| Author | W. S. Sampath |
|---|
| Description | During this quarter, we have progressed on the tasks outlined in our SOW for Phase II. A fixture for automated cooling of the substrate in vacuum has been designed, fabricated, installed and tested. This is needed for optimum processing of the back contact. Large area devices in the form of strips (~0.5 cm X 8 cm.) have been fabricated and tested at NREL. Efficiency of 10.9% has been measured. The air-to-vacuum-to-air seals in the pilot system have a glass filled teflon liner. These liners have experienced wear and this results in scraping of the glass substrates in the seal. Improved liners have been designed and fabricated and are being installed in the system. Based on our current progress, no difficulties are anticipated in successfully completing the future targets outlined in the SOW. A prototype production system to process 16.5x16.5 inch substrates continues to be advanced. This activity is supported by another program from DOE-EERE and cost shared by National Starch and Chemicals (NSC). We are also in discussion with a reputed company to form a strategic partnership to manufacture large volumes of CdTe PV based on our technology. Numerous documents have been submitted to this group for evaluating our technology. These discussions have advanced significantly. |
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| Venue | XXL-5-44205-02 |
|---|
| Source | Colorado State University |
|---|
| Document Type | Quarterly Report (Word document) |
|---|
| Resource Date | 04/2006 |
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|
| Post Date | 02/01/2006 |
|---|
| Title | STUDIES OF BASIC ELECTRONIC PROPERTIES OF CDTE-BASED SOLAR CELLS |
|---|
| Link | (PDF 152 KB) Download Acrobat Reader. |
|---|
| Author | J. Beach |
|---|
| Description | The goal of this deep electronic states (DES) study is to detect, characterize, and identify DES that may be either limiting or enhancing VOC in order to help cell growers modify their processes to improve their devices. A J-V-T, QE, and impedance characterization analysis was performed on cells received from X. Wu that were processed without intentionally added Cu and with three CdCl2 treatments. This compliments a set of previously analyzed cells with added Cu and the same three CdCl2 treatments. This is part of an ongoing collaborative study with Wu. Further analyses are expected with variable Cu and O2 |
|---|
| Venue | CSM Extension of ADJ-2-30630-05, Studies of Basic Electronic Properties of CdTe-based Solar Cells. |
|---|
| Source | Colorado School of Mines, Golden, CO |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 01/31/2006 |
|---|
|
| Post Date | 02/28/2006 |
|---|
| Title | CHARACTERIZATION OF THE ELECTRONIC AND CHEMICAL STRUCTURE AT THIN FILM SOLAR CELL INTERFACES |
|---|
| Link | (PDF 99 KB) Download Acrobat Reader. |
|---|
| Author | C. Heske |
|---|
| Description | This project is devoted to deriving the electronic structure of interfaces in Cu(In,Ga)(S,Se)2 and CdTe thin film solar cells. By using a unique combination of spectroscopic methods (photoelectron spectroscopy, inverse photoemission, and X-ray ab-sorption and emission spectroscopy) a comprehensive picture of the electronic (i.e., band alignment in the valence and conduction band) as well as the chemical structure can be painted. The work focuses on (a) deriving the bench mark picture for world-record cells, (b) analyze state-of-the-art cells from industrial processes, and (c) aid in the troubleshooting of cells with substandard performance. In our recent beamtime at the Advanced Light Source, Lawrence Berkeley National Laboratory we collected first results with Cu(In,Ga)Se2 samples prepared by NREL. Together with additional photoemission measurements a detailed picture of the chemical composition at several interfaces and surfaces of the device structure can be drawn. The setup for inverse photoemission at UNLV was commissioned and first spectra were recorded. |
|---|
| Venue | U. Nevada, Las Vegas, subcontract XXL-5-44205-12, 2nd Quarterly Report |
|---|
| Source | University of Nevada, Las Vegas |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 01/18/2006 |
|---|
|
| Post Date | 12/16/2005 |
|---|
| Title | CHARACTERIZATION AND ANALYSIS OF CIS AND CDTE CELLS |
|---|
| Link | (MS Word 45 KB) |
|---|
| Author | J. R. Sites |
|---|
| Description | CdTe Device Model; Cu in the Back Contact;Back-Illuminated LBIC;
CdTe Photoluminescence; CIGS Thin Absorbers/Back Lighting; Effective Module Efficiency The two key module parameters that control the effective efficiency are the series resistance and leakage conductance of the module; (1) ?Grain-Boundary Recombination in Cu(In,Ga)Se2 Solar Cells,? J. Appl. Phys. 98, 113704, 10 pp (2005). M. Gloeckler, W.K. Metzger, and J.R. Sites.
(2) ?Potential of Sub-micrometer Thickness Cu(In,Ga)Se2 Solar Cells,? J. Appl. Phys. 98, 103703, 7 pp (2005). M. Gloeckler and J.R. Sites. |
|---|
| Venue | Subcontract XXL-5-44205-03 Quarterly Report IV (September - November 2005); : http://www.physics.colostate.edu/groups/photovoltaic |
|---|
| Source | Colorado State University |
|---|
| Document Type | Quarterly Report (Word document) |
|---|
| Resource Date | 12/15/2005 |
|---|
|
| Post Date | 01/11/2006 |
|---|
| Title | FABRICATION AND PHYSICS OF CDTE DEVICES BY SPUTTERING |
|---|
| Link | (PDF 591 KB) Download Acrobat Reader. |
|---|
| Authors | A. Compaan, V. G. Karpov |
|---|
| Description | This progress report covers the third quarter of Phase 1 for the period September 1, 2005, through November 30, 2005, of the above Thin Film Photovoltaic Partnership Program subcontract. During this quarter we worked on thin CdTe solar cell limitations, spatial and temporal variations in electronic transport through a CdTe-based Schottky barrier, device physics modeling, and ellipsometric diagnostics. In this report we highlight our recent results on the distribution of copper in sputtered CdTe solar cells (task 1.3.4) and recently discovered reversible piezo-effect in CdTe/CdS solar cells consistent with the piezo parameters of CdS, which strongly supports our MIS device model (task 1.2.1). |
|---|
| Venue | RXL-5-44205-01 Phase 1/Quarter 3 |
|---|
| Source | University of Toledo |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 12/2005 |
|---|
|
| Post Date | 12/16/2005 |
|---|
| Title | CDTE-BASED SOLAR CELLS |
|---|
| Link | (PDF 670 KB) Download Acrobat Reader. |
|---|
| Author | B. E. McCandless |
|---|
| Description | Alternative Cu-based contact processing for CdTe/CdS devices; Back contact analysis using bifacial CdTe devices; Bifacial Spectral Response Characterization: effect of CdTe thickness |
|---|
| Venue | NREL Subcontract #ADJ-1-30630-12 |
|---|
| Source | University of Delaware |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 11/30/2005 |
|---|
|
| Post Date | 10/21/2005 |
|---|
| Title | CHARACTERIZATION OF THE ELECTRONIC AND CHEMICAL STRUCTURE AT THIN FILM SOLAR CELL INTERFACES |
|---|
| Link | (PDF 414 KB) Download Acrobat Reader. |
|---|
| Author | C. Heske |
|---|
| Description | This project is devoted to deriving the electronic structure of interfaces in Cu(In,Ga)(S,Se)2 and CdTe thin film solar cells. By using a unique combination of spectroscopic methods (photoelectron spectroscopy, inverse photoemission, and X-ray ab-sorption and emission) a comprehensive picture of the electronic (i.e., band alignment in the valence and conduction band) as well as chemical structure can be painted. The work focuses on (a) deriving the bench mark picture for world-record cells, (b) analyze state-of-the-art cells from industrial processes, and (c) aid in the troubleshooting of cells with substandard performance. |
|---|
| Venue | subcontract quarterly report, U. Nevada, Las Vegas, XXL-5-44205-12 |
|---|
| Source | University of Nevada, Las Vegas |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 10/13/2005 |
|---|
|
| Post Date | 09/13/2005 |
|---|
| Title | CHARACTERIZATION AND ANALYSIS OF CIS AND CDTE CELLS |
|---|
| Link | (MS Word 44 KB) |
|---|
| Author | J. R. Sites |
|---|
| Description | During the past quarter, we made progress in several areas as outlined below. I am particularly pleased that the two students who completed their PhD this year have accepted R&D positions in the US thin-film photovoltaic industry. Alex Pudov starts at Nanosolar in Palo Alto this week, and Markus Gloeckler will be joining First Solar in Toledo in early October. |
|---|
| Venue | Quarterly Report III (June - August 2005) Subcontract XXL-5-44205-03 |
|---|
| Source | Colorado State University |
|---|
| Document Type | Quarterly Report (Word document) |
|---|
| Resource Date | 09/12/2005 |
|---|
|
| Post Date | 09/30/2005 |
|---|
| Title | FABRICATION AND PHYSICS OF CDTE DEVICES BY SPUTTERING |
|---|
| Link | (PDF 605 KB) Download Acrobat Reader. |
|---|
| Authors | A. Compaan, V. G. Karpov |
|---|
| Description | This progress report covers the second quarter of Phase 1 for the period June 1, 2005, through August 31, 2005, of the above Thin Film Photovoltaic Partnership Program subcontract. During this quarter we worked on spatial and temporal variations in electronic transport through a CdTe-based Schottky barrier, ellipsometric diagnostics, device physics modeling, and thin CdTe solar cell limitations. In this report we highlight our recent results on optical spectroscopy of deep levels in CdTe single crystal (task 1.3.1) and analysis of structural evolution during growth of CdS and CdTe from real time spectroscopic ellipsometry (task 1.3.2) |
|---|
| Venue | RXL-5-44205-01 Phase 1/Quarter 2 |
|---|
| Source | University of Toledo |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 09/2005 |
|---|
|
| Post Date | 10/05/2005 |
|---|
| Title | CSU 3RD Q REPORT |
|---|
| Link | (MS Word 103 KB) |
|---|
| Author | W. S. Sampath |
|---|
| Description | During this quarter, we have progressed on the tasks outlined in our SOW for Phase I. A significant extension to our pilot scale system has been designed, fabricated, installed and debugged. This will allow improved process conditions for the back contact process steps. The feasibility of cooling the substrate in vacuum for optimum processing of the back contact has been demonstrated. A large number of experiments have been performed on laser scribing of CdS/CdTe films. Mechanical scribing has yielded the lowest contact resistance between the scribed region and the metallization, to date. Researchers at National Starch and Chemicals (NSC) have performed many experiments to screen print carbon, nickel and silver films in patterns. The adhesion of these films was tested according to ASTM 3359B and achieved a 5B or "excellent" rating. Based on our current progress, no difficulties are anticipated in successfully completing the future targets outlined in the SOW. The nominal 2 MW/yr production prototype system continues to be advanced. This activity is supported by another program from DOE-EERE and cost shared by National Starch and Chemicals (NSC). Three separate groups have expressed interest in licensing our technology for 50 MW/Yr plants. We are also in discussion with a large manufacturer for partnership to manufacture large volumes of CdTe PV. Numerous documents have been submitted to these groups for evaluating our technology. Detailed presentations and demonstrations of our technology were also given to many groups. |
|---|
| Venue | Thin Film Partnership Program (Subcontract No. XXL-5-44205-02 |
|---|
| Source | Colorado State University |
|---|
| Document Type | Quarterly Report (Word document) |
|---|
| Resource Date | 09/2005 |
|---|
|
| Post Date | 09/13/2005 |
|---|
| Title | DEVELOPMENT OF A WIDE BAND GAP CELL FOR THIN FILM TANDEM SOLAR CELLS |
|---|
| Link | (PDF 64 KB) Download Acrobat Reader. |
|---|
| Author | R. W. Birkmire |
|---|
| Description | CdZnTe and CIGS alloys |
|---|
| Venue | XAT-4-33624-01 6th Quarterly Report |
|---|
| Source | University of Delaware |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 09/2005 |
|---|
|
| Post Date | 08/31/2005 |
|---|
| Title | ADVANCED PROCESSING OF CDTE- AND CUINXGA1-XSE2 |
|---|
| Link | (PDF 325 KB) Download Acrobat Reader. |
|---|
| Author | C. S. Ferekides |
|---|
| Description | quarter of Phase III of the above subcontract. The project deals with two thin film technologies: CdTe and CIGS. The focus areas include: (a) CdTe ? stability, novel back/front contacts, and the development of manufacturing friendly processes; (b) CIGS ? development of two-step non-co-evaporation technology.This is the progress report for the 3rd |
|---|
| Venue | NDJ-2-30630-18 Phase III/Quarter 3 |
|---|
| Source | University of South Florida, Tampa |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 08/2005 |
|---|
|
| Post Date | 08/02/2005 |
|---|
| Title | IEC MONTHLY REPORT: CDTE |
|---|
| Link | (PDF 2.1 MB) Download Acrobat Reader. |
|---|
| Author | B. E. McCandless |
|---|
| Description | Different aspects of processing vapor transport (VT) solar cells were evaluated and new processing options to address key issues of high throughput are being developed. In particular, variations in device performance are correlated with systematic variations in the CdCl2 treatment and with the exposure of fresh CdTe surfaces to humid ambient prior to CdCl2 treatment. With respect to CdTe deposition, characterization of the VT deposition system was carried out to refine the quantitative model used to monitor deposition rate and Cd utilization. With respect to surface treatments for back contact processing; alternatives to BDH processing, such as aniline treatment, continue to be investigated. Temperature dependant bifacial QE measurements gave new insights into the CdTe device physics. The formation rate and composition of oxide phases in CdTe films was investigated with respect to humidity. Participation in the National CdTe R&D Team meeting held in May 2005 is described. |
|---|
| Venue | ADJ-1-30630-12 |
|---|
| Source | University of Delaware |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 08/01/2005 |
|---|
|
| Post Date | 08/31/2005 |
|---|
| Title | FABRICATION AND PHYSICS OF CDTE DEVICES BY SPUTTERING |
|---|
| Link | (PDF 529 KB) Download Acrobat Reader. |
|---|
| Authors | A. Compaan, V. G. Karpov |
|---|
| Description | During this quarter we worked on ellipsometric diagnostics, device physics modeling and thin CdTe solar cell limitations. In this report we highlight our recent results on real-time spectroscopic ellipsometry studies of rf-sputtered solar cells (task 1.3.2) and quantitative estimates of nonuniformity loss in solar cell modules, including the effect of series resistance. |
|---|
| Venue | RXL-5-44205-01 Phase 1/Quarter 1 |
|---|
| Source | University of Toledo |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 08/2005 |
|---|
|
| Post Date | 07/26/2005 |
|---|
| Title | RESEARCH LEADING TO HIGH THROUGHPUT MANUFACTURING OF THIN-FILM CDTE PV MODULES |
|---|
| Link | (MS Word 165 KB) |
|---|
| Authors | R. C. Powell, P. V. Meyers |
|---|
| Description | Reactor Design
Advanced Front Contacts
ChlorineIssues
Back-Contact Issues
Stabilitiy Issues
Third Level Metrics |
|---|
| Venue | RDJ-2-30630-20 (); Q11 Quarterly Report |
|---|
| Source | First Solar, Toledo, OH |
|---|
| Document Type | Quarterly Report (Word document) |
|---|
| Resource Date | 07/15/2005 |
|---|
|
| Post Date | 08/04/2005 |
|---|
| Title | BARRIER COATINGS AND STABILITY OF THIN FILM SOLAR CELLS |
|---|
| Link | (MS Word 3.4 MB) |
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| Author | L. Olsen |
|---|
| Description | Work concentrated on studies concerning encapsulation of CdTe cells. Three topics are discussed: further consideration of results for a CSU cell encapsulated with a single dyad/Al-film combination; results for studies of stressed bare cell cells from CSU and University of Toledo; and studies of encapsulated calcium samples subjected to heat and humidity conditions. |
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| Venue | 3rd Quarterly Report - Phase I: March 1, 2005 -- May 31, 2005 |
|---|
| Source | Pacific Northwest National Lab (PNNL) |
|---|
| Document Type | Quarterly Report (Word document) |
|---|
| Resource Date | 07/2005 |
|---|
|
| Post Date | 06/14/2005 |
|---|
| Title | CHARACTERIZATION AND ANALYSIS OF CIS AND CDTE CELLS |
|---|
| Link | (MS Word 46 KB) |
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| Author | J. R. Sites |
|---|
| Description | During the past quarter, we reported a number of results at both the Materials Research Society Spring Meeting in late March and the CdTe National Team Meeting in early May. Most of the manuscripts or powerpoint slides from these and other presentations are available on our web site: www.physics.colostate.edu/groups/photovoltaic In addition, Markus Gloeckler recently completed his PhD degree. His thesis, which is both attached and on the web page, contains a more extensive description of his work on CIGS grain boundaries, grading effects, and efficiency limitations than that published or submitted for publication. |
|---|
| Venue | Quarterly Report II (March - May 2005) Subcontract XXL-5-44205-03 |
|---|
| Source | Colorado State University |
|---|
| Document Type | Quarterly Report (Word document) |
|---|
| Resource Date | 06/13/2005 |
|---|
|
| Post Date | 07/15/2005 |
|---|
| Title | QUARTERLY REPORT CDTE |
|---|
| Link | (MS Word 80 KB) |
|---|
| Author | W. S. Sampath |
|---|
| Description | During this quarter, we have progressed on the tasks outlined in our SOW for Phase I. The reproducibility of device efficiency and stability results during long duration operation of the pilot system with a single charge loading for the CdS, CdTe and CdCl2 processes has been reported earlier by us [1]. Currently, efforts are underway to advance the back contact processing to this same level of reproducibility, as outlined in the SOW. In order to accomplish this, a significant upgrade to increase the processing space in our pilot scale system has been designed, fabricated and is currently being installed. A series of detailed studies on the effect of oxygen during the CdCl2 treatment has been performed. Oxygen has been shown to improve the effectiveness of the CdCl2 treatment. Preliminary results on developing a module interconnection process are promising. Many devices and CdS/CdTe films have been provided to many groups including Larry Olsen of PNNL. Based on our current progress, no difficulties are anticipated in successfully completing the future targets outlined in the SOW. A loadlock system for the prototype production system to transport 16.5x16.5 inch substrates has been designed, constructed and successfully tested. This activity is supported by another program from DOE-EERE and cost shared by National Starch and Chemicals (NSC). Three separate groups including Lisa Barnett from DOE headquarters, Bolko Von Roedern of NREL, Dave Miles from NSC and other representatives from DOE, Peter Meyers and Roger Green of First Solar, and members of the Fort Collins business community were all given a detailed tour of our facilities. Detailed presentations and demonstrations of our technology were also given. |
|---|
| Venue | XXL-5-44205-02 |
|---|
| Source | Colorado State University |
|---|
| Document Type | Quarterly Report (Word document) |
|---|
| Resource Date | 06/2005 |
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|
| Post Date | 06/27/2005 |
|---|
| Title | BARRIER COATINGS AND STABILITY OF THIN FILM SOLAR CELLS |
|---|
| Link | (MS Word 1.8 MB) |
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| Author | L. Olsen |
|---|
| Description | The key objectives of the program are to develop low cost barrier coatings for CIS and CdTe solar cells and to develop an improved understanding of the effects of water on the stability of these types of cells. The scope of this work entails investigations of multilayer, barrier coatings for CIS and CdTe thin film solar cells, and studies of stability issues, particularly those related to moisture ingress. Investigation of barrier coatings on SSI and CSU devices will continue in an effort to establish effective approaches to encapsulate CIS and CdTe modules. Studies will also be directed towards issues concerning cost of the coating process. The program will be structured into three major tasks: (1) Barrier coatings and stability studies for CIS Solar Cells; (2) Barrier coatings and stability studies for CdTe solar cells; (3) Low cost coating process development. |
|---|
| Venue | 2nd Quarterly Report - Phase I: December 1, 2004 -- February 28, 2005 |
|---|
| Sources | Colorado State University; Pacific Northwest National Lab (PNNL) |
|---|
| Document Type | Quarterly Report (Word document) |
|---|
| Resource Date | 06/2005 |
|---|
|
| Post Date | 05/20/2005 |
|---|
| Title |
ADVANCED PROCESSING OF CDTE- AND CUIN XGA1-XSE2 |
|---|
| Link | (PDF 277 KB) Download Acrobat Reader. |
|---|
| Authors | C. S. Ferekides, D. Morel |
|---|
| Description | This is the progress report for the 2nd quarter of Phase III of the above subcontract. The project deals with two thin film technologies: CdTe and CIGS. The focus areas include: (a) CdTe ? stability, novel back/front contacts, and the development of manufacturing friendly processes;
(b) CIGS ? development of two-step non-co-evaporation technology. |
|---|
| Venue |
NDJ-2-30630-18 Phase III/Quarter 2 |
|---|
| Source | University of South Florida, Tampa |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 05/2005 |
|---|
|
| Post Date | 05/13/2005 |
|---|
| Title | CENTER OF EXCELLENCE |
|---|
| Link | (PDF 529 KB) Download Acrobat Reader. |
|---|
| Authors | R. W. Birkmire, B. E. McCandless |
|---|
| Description | This report covers research conducted at the Institute of Energy Conversion (IEC) for the period from March 3, 2005 to April 3, 2005, under the subject subcontract. The report highlights progress and results obtained under Task 1 (CdTe-based solar cells). |
|---|
| Venue | ADJ-1-30630-12 |
|---|
| Source | University of Delaware |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 04/2005 |
|---|
|
| Post Date | 04/05/2005 |
|---|
| Title | SUBCONTRACT NO. XXL-5-44205-02 TO COLORADO STATE UNIVERSITY |
|---|
| Link | (MS Word 70 KB) |
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| Author | W. S. Sampath |
|---|
| Description | During this quarter, we have progressed on the tasks outlined in our SOW for Phase I. Reproducibility of device efficiency and stability has been demonstrated during long duration operation of the system with a single charge loading for the CdS, CdTe and CdCl2 process. Currently efforts are underway to advance the back contact processing to the same level as outlined in the SOW. Preliminary results on interconnection have yielded very promising results. Mathematical modeling of a package design has yielded results that show that moisture can be kept from our device for 22 years at 65C temperature with saturated humidity. Hardware to perform steady state photocapacitance (PHCAP) has been designed, built and tested in our laboratory. The effect of processing on the deep states in CdTe devices can be seen quantitatively. Optimum process conditions lead to lower photocapacitance signals. Many devices and CdS/CdTe samples have been provided to many groups including Larry Olsen of PNNL. Based on our current progress, no difficulties are anticipated in successfully completing the future targets outlined in the SOW. In addition to the tasks outlined above, two members of our team attended the 31st IEEE PVSC. Two oral presentations (preprints were sent to you earlier) were given. In addition, a poster was presented at the ICTMC conference and this paper has been accepted for publication in a journal. A loadlock system for the 16" X 16" substrates has been designed and constructed and is being tested. This activity is supported by another program from DOE-EERE and cost shared by NSC. Two scientists from GE Global Research were given a detailed tour of our facilities and a detailed presentation of our technology was made. |
|---|
| Venue | XXL-5-44205-02 |
|---|
| Source | Colorado State University |
|---|
| Document Type | Quarterly Report (Word document) |
|---|
| Resource Date | 03/28/2005 |
|---|
|
| Post Date | 03/22/2005 |
|---|
| Title | QUARTERLY REPORT I (DECEMBER 2004 - FEBRUARY 2005) "CHARACTERIZATION AND ANALYSIS OF CIS AND CDTE CELLS" SUBCONTRACT XXL-5-44205-03 |
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| Link | (MS Word 39 KB) |
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| Author | J. R. Sites |
|---|
| Description | CIGS grain boundaries; thins CIGS grading; secondary CIGS junction barriers; Alternative junctions with CIGS; Cdte Cell Operation, LBIC Studies, PL Studies |
|---|
| Venue | |
|---|
| Source | Colorado State University |
|---|
| Document Type | Quarterly Report (Word document) |
|---|
| Resource Date | 03/21/2005 |
|---|
|
| Post Date | 04/18/2005 |
|---|
| Title | RESEARCH LEADING TO HIGH THROUGHPUT MANUFACTURING OF THIN-FILM CDTE PV MODULES |
|---|
| Link | (MS Word 66 KB) |
|---|
| Author | R. C. Powell |
|---|
| Description | We completed the move from Technology Center facilities at Eckel Junction Road. All development personnel and equipment is now located at the Cedar Park facility. Nearly all of the equipment has been installed and is operational. We expect the move to improve the effectiveness of the Technology Development Team |
|---|
| Venue | subcontract rdj-2-30630-20 |
|---|
| Source | First Solar, Toledo, OH |
|---|
| Document Type | Quarterly Report (Word document) |
|---|
| Resource Date | 02/15/2005 |
|---|
|
| Post Date | 02/17/2005 |
|---|
| Title | RESEARCH LEADING TO HIGH THROUGHPUT MANUFACTURING OF THIN-FILM CDTE PV MODULES |
|---|
| Link | (MS Word 85 KB) |
|---|
| Author | R. C. Powell |
|---|
| Description | |
|---|
| Venue | RDJ-2-30630-20 |
|---|
| Source | First Solar, Toledo, OH |
|---|
| Document Type | Quarterly Report (Word document) |
|---|
| Resource Date | 02/15/2005 |
|---|
|
| Post Date | 05/13/2005 |
|---|
| Title | CENTER OF EXCELLENCE |
|---|
| Link | (PDF 757 KB) Download Acrobat Reader. |
|---|
| Authors | R. W. Birkmire, B. E. McCandless |
|---|
| Description | This report covers research conducted at the Institute of Energy Conversion (IEC) for the period from Dec. 04, 2004 to Jan. 03, 2005, under the subject subcontract. The report highlights progress and results obtained under Task 1 (CdTe-based solar cells). |
|---|
| Venue | ADJ-1-30630-12 |
|---|
| Source | University of Delaware |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 01/2005 |
|---|
|
| Post Date | 02/14/2005 |
|---|
| Title | BARRIER COATINGS AND STABILITY OF THIN FILM SOLAR CELLS |
|---|
| Link | (MS Word 2.5 MB) |
|---|
| Author | L. Olsen |
|---|
| Description | |
|---|
| Venue | |
|---|
| Source | Pacific Northwest National Lab (PNNL) |
|---|
| Document Type | Quarterly Report (Word document) |
|---|
| Resource Date | 12/2004 |
|---|
|
| Post Date | 02/14/2005 |
|---|
| Title | BARRIER COATINGS AND STABILITY OF THIN FILM SOLAR CELLS |
|---|
| Link | (MS Word 2.5 MB) |
|---|
| Author | L. Olsen |
|---|
| Description | Investigations of approaches for applying barrier coatings to CdTe cells from Dr. Sampath's group at Colorado State University (CSU) continued this past quarter. After reviewing our approach to coating the CSU cells, results of accelerated stress tests are given. |
|---|
| Venue | 1st Quarterly Report - Phase I: September 1, 2004 — November 30, 2004 |
|---|
| Source | Pacific Northwest National Lab (PNNL) |
|---|
| Document Type | Quarterly Report (Word document) |
|---|
| Resource Date | 12/2004 |
|---|
|
| Post Date | 02/08/2005 |
|---|
| Title | STUDIES OF BASIC ELECTRONIC PROPERTIES OF CDTE-BASED SOLAR CELLS & THEIR EVOLUTION DURING PROCESSING & STRESS |
|---|
| Link | (MS Word 1.9 MB) |
|---|
| Author | V. Kaydanov |
|---|
| Description | CdTe/CdS obtained in the past four months in the following areas: Studies of electroluminescence intensity and pattern in differently processes and treated cellsStudies of deep electronic states (DES) with admittance spectroscopy and transient measurements; analysis and classification of the DES signaturesMapping photocurrent collection over a cell area with the high resolution near field scanning optical microscopy (NSOM) |
|---|
| Venue | NREL report |
|---|
| Source | Colorado School of Mines, Golden, CO |
|---|
| Document Type | Quarterly Report (Word document) |
|---|
| Resource Date | 10/2004 |
|---|
|
| Post Date | 03/03/2005 |
|---|
| Title | DEVICE PHYSICS OF THIN-FILM POLYCRYSTALLINE SOLAR CELLS |
|---|
| Link | (MS Word 30 KB) |
|---|
| Author | J. R. Sites |
|---|
| Description | |
|---|
| Venue | ADJ-1-30630-06 |
|---|
| Source | Colorado State University |
|---|
| Document Type | Quarterly Report (Word document) |
|---|
| Resource Date | 09/07/2004 |
|---|
|
| Post Date | 03/03/2005 |
|---|
| Title | DEVELOPMENT OF A WIDE BAND GAP CELL FOR THIN FILM TANDEM SOLAR CELLS |
|---|
| Link | (PDF 856 KB) Download Acrobat Reader. |
|---|
| Author | R. W. Birkmire |
|---|
| Description | |
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| Venue | XAT-4-33624-01 |
|---|
| Source | University of Delaware |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 09/2004 |
|---|
|
| Post Date | 02/09/2005 |
|---|
| Title | BARRIER COATINGS AND STABILITY OF THIN FILM SOLAR CELLS |
|---|
| Link | (MS Word 62 KB) |
|---|
| Author | L. Olsen |
|---|
| Description | Efforts this past quarter concentrated on developing approaches to applying barrier coatings to CdTe cells from Dr. Sampath's group at Colorado State University (CSU) and carrying out accelerated testing of the cells. |
|---|
| Venue | 4th Quarterly Report - Phase II: June 1, 2004 — August 31, 2004 |
|---|
| Source | Pacific Northwest National Lab (PNNL) |
|---|
| Document Type | Quarterly Report (Word document) |
|---|
| Resource Date | 09/2004 |
|---|
|
| Post Date | 05/10/2005 |
|---|
| Title | NREL SUBCONTRACT # ADJ-1-30630-12 |
|---|
| Link | (PDF 437 KB) Download Acrobat Reader. |
|---|
| Author | R. W. Birkmire |
|---|
| Description | a-Si and CdTe |
|---|
| Venue | |
|---|
| Source | University of Delaware |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 08/23/2004 |
|---|
|
| Post Date | 02/09/2005 |
|---|
| Title | RESEARCH LEADING TO HIGH THROUGHPUT MANUFACTURING OF THIN-FILM CDTE PV MODULES |
|---|
| Link | (MS Word 108 KB) |
|---|
| Author | R. C. Powell |
|---|
| Description | Progress |
|---|
| Venue | NREL report Q7 RDJ-2-30630-20 |
|---|
| Source | First Solar, Toledo, OH |
|---|
| Document Type | Quarterly Report (Word document) |
|---|
| Resource Date | 07/19/2004 |
|---|
|
| Post Date | 02/08/2005 |
|---|
| Title | CSU PHASE III Q3 |
|---|
| Link | (PDF 100 KB) Download Acrobat Reader. |
|---|
| Author | W. S. Sampath |
|---|
| Description | Significant advancements have been made in demonstrating a process for consistently fabricating stable CdTe PV. During the past few months, the optimum, baseline absorber/CdClz. |
|---|
| Venue | Subcontract No. ADJ-1-30630-07 |
|---|
| Source | Colorado State University |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 06/22/2004 |
|---|
|
| Post Date | 02/09/2005 |
|---|
| Title | CDTE-BASED SOLAR CELLS |
|---|
| Link | (PDF 45 KB) Download Acrobat Reader. |
|---|
| Author | B. E. McCandless |
|---|
| Description | |
|---|
| Venue | ADJ-1-30630-12 |
|---|
| Source | University of Delaware |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 06/21/2004 |
|---|
|
| Post Date | 02/09/2005 |
|---|
| Title | SI AND DIAGNOSTICS |
|---|
| Link | (PDF 239 KB) Download Acrobat Reader. |
|---|
| Author | R. W. Birkmire |
|---|
| Description | |
|---|
| Venue | ADJ-1-30630-12 |
|---|
| Source | University of Delaware |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 06/03/2004 |
|---|
|
| Post Date | 02/08/2005 |
|---|
| Title | STUDIES OF BASIC ELECTRONIC PROPERTIES OF CDTE-BASED SOLAR CELLS & THEIR EVOLUTION DURING PROCESSING & STRESS |
|---|
| Link | (MS Word 364 KB) |
|---|
| Authors | V. Kaydanov, et al. |
|---|
| Description | Previously we have reported some differences in the EL and Pl spectra obtained from the same small area of a cell, as well as some features of the spectra that supposedly could be attributed to Cu related defects [1, 2]. Here we present results of new comparative studies on differently processed cells: (a) cells intentionally doped non-uniformly with Cu and subjected to wet or dry treatments with CdCl2 of different purity; (b) prepared at CSU with and without Cu-doping. |
|---|
| Venue | NREL quarterly report |
|---|
| Source | Colorado School of Mines, Golden, CO |
|---|
| Document Type | Quarterly Report (Word document) |
|---|
| Resource Date | 06/2004 |
|---|
|
| Post Date | 02/09/2005 |
|---|
| Title | DEVELOPMENT OF A WIDE BAND GAP CELL FOR THIN FILM TANDEM SOLAR CELLS |
|---|
| Link | (PDF 700 KB) Download Acrobat Reader. |
|---|
| Author | N/A |
|---|
| Description | Much of the work this quarter continued to focus on the relative incorporation of S and Se during CuIn(SeS)2 or Cu(InGa)(SeS)2 deposition. In the previous quarterly report, we showed that the re was a reproducible difference between films grown with Cu-rich composition and those with Cu-poor composition. Films deposited with Cu/(In+Ga) > 1.1 preferentially incorporate S, while those with Cu/(In+Ga) < 0.9 preferentially incorporate Se. This is shown in Figure 1, which plots the relative S and Se incorporation in films, as measured by EDS, as a function of the S/(S+Se) ratio in the vapor, determined by the average effusion rate measured for each source during the run. For both the Cu-rich and Cu-poor cases, there is no correlation with Ga/(In+Ga) and data is included for CuIn(SeS)2 films as well as Cu(InGa)(SeS)2 with different Ga/(In+Ga). Post-deposition KCN etching, to remove a surface Cux (SeS)y... |
|---|
| Venue | 2nd Quarterly Report XAT-4-33624-01 |
|---|
| Source | University of Delaware |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 05/05/2004 |
|---|
|
| Post Date | 03/03/2005 |
|---|
| Title | DEVICE PHYSICS OF THIN-FILM POLYCRYSTALLINE SOLAR CELLS |
|---|
| Link | (MS Word 35 KB) |
|---|
| Author | J. R. Sites |
|---|
| Description | |
|---|
| Venue | ADJ-1-30630-06 |
|---|
| Source | Colorado State University |
|---|
| Document Type | Quarterly Report (Word document) |
|---|
| Resource Date | 03/05/2004 |
|---|
|
| Post Date | 02/08/2005 |
|---|
| Title | DEVICE PHYSICS OF THIN-FILM POLYCRYSTALLINE SOLAR CELLS |
|---|
| Link | (MS Word 35 KB) |
|---|
| Author | J. R. Sites |
|---|
| Description | Measurement and analysis. |
|---|
| Venue | NREL Q10 ADJ-1-30630-06 |
|---|
| Source | Colorado State University |
|---|
| Document Type | Quarterly Report (Word document) |
|---|
| Resource Date | 03/05/2004 |
|---|
|
| Post Date | 02/09/2005 |
|---|
| Title | HIGH-EFFICIENCY CADMIUM-TELLURIDE THIN-FILM SOLAR CELLS |
|---|
| Link | (PDF 320 KB) Download Acrobat Reader. |
|---|
| Author | A. Compaan |
|---|
| Description | The report describes our activities and progress in understanding of the effects of the back contact on device open-circuit voltage and efficiency. We propose a new structure for fabricating efficient CdTe/CdS solar cells (in the range of 13%) without Cu doping or post-metal heat treatments. Also, we describe the results of our study of synchrotron xray absorption fine structure (XAFS) aimed at understanding the role of diffused copper in CdCl2 treated CdTe. |
|---|
| Venue | NDJ-1-30630-02 Phase 3/Quarter 2 |
|---|
| Source | University of Toledo |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 03/2004 |
|---|
|
| Post Date | 02/10/2005 |
|---|
| Title | ADVANCED PROCESSING OF CDTE- AND CUINXGA1-XSE2- |
|---|
| Link | (PDF 189 KB) Download Acrobat Reader. |
|---|
| Authors | C. S. Ferekides, D. Morel |
|---|
| Description | The focus areas include: (a) CdTe ? stability, novel back/front contacts, and the development of manufacturing friendly processes; (b) CIGS ? development of two-step non-co-evaporation technology. |
|---|
| Venue | NDJ-2-30630-18 Phase III/Quarter 1 |
|---|
| Source | University of South Florida, Tampa |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 03/2004 |
|---|
|
| Post Date | 02/08/2005 |
|---|
| Title | STUDIES OF BASIC ELECTRONIC PROPERTIES OF CDTE-BASED SOLAR CELLS & THEIR EVOLUTION DURING PROCESSING & STRESS |
|---|
| Link | (MS Word 747 KB) |
|---|
| Author | V. Kaydanov |
|---|
| Description | Our previous studies demonstrated high sensitivity of EL intensity and pattern to the CdTe cell processing and stressing (see, e.g., [1]). In particular, it was found that even a "gentle" stress can significantly effect measured EL whereas the J-V characterization detects only slight changes. EL imaging of a cell proved useful to reveal micro-nonuniformities in electronic properties and clarify mechanisms behind them. Deep states... |
|---|
| Venue | NREL quarterly |
|---|
| Source | Colorado School of Mines, Golden, CO |
|---|
| Document Type | Quarterly Report (Word document) |
|---|
| Resource Date | 02/2004 |
|---|
|
| Post Date | 01/18/2004 |
|---|
| Title | RESEARCH LEADING TO HIGH THROUGHPUT MANUFACTURING OF THIN-FILM CDTE PV MODULES |
|---|
| Link | (MS Word 784 KB) |
|---|
| Author | R. C. Powell |
|---|
| Description | Reactor development, uniformity issues, stress testing, back contact improvement |
|---|
| Venue | First Solar: RDJ-2-30630-20; Q5 NREL Quarterly Report |
|---|
| Source | First Solar, Toledo, OH |
|---|
| Document Type | Quarterly Report (Word document) |
|---|
| Resource Date | 01/15/2004 |
|---|
|
| Post Date | 02/09/2005 |
|---|
| Title | RESEARCH LEADING TO HIGH THROUGHPUT MANUFACTURING OF THIN-FILM CDTE PV MODULES |
|---|
| Link | (MS Word 784 KB) |
|---|
| Author | R. C. Powell |
|---|
| Description | Progress report. |
|---|
| Venue | NREL report Q5 RDJ-2-30630-20 |
|---|
| Source | First Solar, Toledo, OH |
|---|
| Document Type | Quarterly Report (Word document) |
|---|
| Resource Date | 01/15/2004 |
|---|
|
| Post Date | 02/09/2005 |
|---|
| Title | CDTE SOLAR CELLS |
|---|
| Link | (PDF 1.7 MB) Download Acrobat Reader. |
|---|
| Author | R. W. Birkmire |
|---|
| Description | Progress |
|---|
| Venue | ADJ-1-30630-12 |
|---|
| Source | University of Delaware |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 12/23/2003 |
|---|
|
| Post Date | 02/10/2005 |
|---|
| Title | RESEARCH LEADING TO HIGH THROUGHPUT MANUFACTURING OF THIN-FILM CDTE PV MODULES |
|---|
| Link | (MS Word 2.2 MB) |
|---|
| Authors | V. G. Karpov, D. Shvydka |
|---|
| Description | The report describes our activities in mapping and modeling large area CdTe PV modules. Here we describe our estimate of nonuniformity related loss. |
|---|
| Venue | RDJ-2-30630-20 |
|---|
| Source | University of Toledo |
|---|
| Document Type | Quarterly Report (Word document) |
|---|
| Resource Date | 12/2003 |
|---|
|
| Post Date | 02/10/2005 |
|---|
| Title | THE FABRICATION AND PHYSICS OF HIGH-EFFICIENCY CADMIUM ? TELLURIDE THIN-FILM SOLAR CELLS |
|---|
| Link | (PDF 320 KB) Download Acrobat Reader. |
|---|
| Authors | A. Compaan, V. G. Karpov |
|---|
| Description | This report describes our activities and progress in making CdTe devices by different techniques and understanding their characteristics. More specifically, it describes our recently developed understanding of buffer layer effects, modeling of integrated large-area modules in progress, and our latest efforts in ion implantation (chlorine) and the related changes in photoluminescence (PL). |
|---|
| Venue | NDJ-1-30630-02 Phase 3/Quarter 1 |
|---|
| Source | University of Toledo |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 12/2003 |
|---|
|
| Post Date | 02/09/2005 |
|---|
| Title | ADVANCED PROCESSING OF CDTE- AND CUINXGA1-XSE2- BASED SOLAR CELLS |
|---|
| Link | (MS Word 497 KB) |
|---|
| Authors | C. S. Ferekides, D. Morel |
|---|
| Description | The focus areas include: (a) CdTe ? stability, novel back/front contacts, and the development of manufacturing friendly processes; (b) CIGS ? development of two-step non-co-evaporation technology... |
|---|
| Venue | NDJ-2-30630-18 Phase II/Quarter 3 |
|---|
| Source | University of South Florida, Tampa |
|---|
| Document Type | Quarterly Report (Word document) |
|---|
| Resource Date | 11/2003 |
|---|
|
| Post Date | 02/10/2005 |
|---|
| Title | RESEARCH LEADING TO HIGH THROUGHPUT MANUFACTURING OF THIN-FILM CDTE PV MODULES |
|---|
| Link | (MS Word 606 KB) |
|---|
| Authors | V. G. Karpov, D. Shvydka |
|---|
| Description | The report describes our activities in mapping and modeling large area CdTe PV modules. Here we describe some examples of mapping and PSPICE modeling. |
|---|
| Venue | RDJ-2-30630-20 |
|---|
| Source | University of Toledo |
|---|
| Document Type | Quarterly Report (Word document) |
|---|
| Resource Date | 09/2003 |
|---|
|
| Post Date | 02/08/2005 |
|---|
| Title | STUDIES OF BASIC ELECTRONIC PROPERTIES OF CDTE-BASED SOLAR CELLS & THEIR EVOLUTION DURING PROCESSING & STRESS |
|---|
| Link | (PDF 497 KB) Download Acrobat Reader. |
|---|
| Author | V. Kaydanov |
|---|
| Description | New instrumentation for acquisition of high spatial-resolution imaging electroluminescence (EL) with spectroscopic measurements on the same length scale. Results are presented for samples that have intentional non-uniformity due to back contact preparation. We also completed analysis of the newly-named Gas Jet Deposition system (GJD), previously called Jet Vapor Deposition (JVD). |
|---|
| Venue | NREL ADJ-2-30630-05 |
|---|
| Source | Colorado School of Mines, Golden, CO |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 08/2003 |
|---|
|
| Post Date | 02/09/2005 |
|---|
| Title | ADVANCED PROCESSING OF CDTE- AND CUINXGA1-XSE- BASED SOLAR CELLS |
|---|
| Link | (MS Word 3.1 MB) |
|---|
| Authors | C. S. Ferekides, D. Morel |
|---|
| Description | The focus areas include: (a) CdTe ? stability, novel back/front contacts, and the development of manufacturing friendly processes; (b) CIGS ? development of two-step non-co-evaporation technology. |
|---|
| Venue | NDJ-2-30630-18 Phase II/Quarter 2 |
|---|
| Source | University of South Florida, Tampa |
|---|
| Document Type | Quarterly Report (Word document) |
|---|
| Resource Date | 08/2003 |
|---|
|
| Post Date | 02/09/2005 |
|---|
| Title | SI-BASED SOLAR CELLS AND DIAGNOSTICS |
|---|
| Link | (PDF 47 KB) Download Acrobat Reader. |
|---|
| Author | R. W. Birkmire |
|---|
| Description | |
|---|
| Venue | ADJ-1-30630-12 |
|---|
| Source | University of Delaware |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 07/24/2003 |
|---|
|
| Post Date | 02/09/2005 |
|---|
| Title | POLYCRYSTALLINE THIN-FILM TANDEM PHOTOVOLTAIC CELLS |
|---|
| Link | (PDF 1.6 MB) Download Acrobat Reader. |
|---|
| Author | A. Compaan |
|---|
| Description | Sputter deposition and vapor transport deposition of II-VI semiconductors for exploratory development of four-terminal and two-terminal tandem solar cells based on CdTe alloys for top cells. |
|---|
| Venue | Phase 2, Q3 |
|---|
| Source | University of Toledo |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 06/30/2003 |
|---|
|
| Post Date | 03/04/2005 |
|---|
| Title | SUBCONTRACT ADJ-1-30630-06 |
|---|
| Link | (MS Word 27 KB) |
|---|
| Author | J. R. Sites |
|---|
| Description | cell modeling |
|---|
| Venue | |
|---|
| Source | Colorado State University |
|---|
| Document Type | Quarterly Report (Word document) |
|---|
| Resource Date | 06/09/2003 |
|---|
|
| Post Date | 02/08/2005 |
|---|
| Title | QUARTERLY REPORT VII (MARCH - MAY 2003) SUBCONTRACT ADJ-1-30630-06 |
|---|
| Link | (MS Word 29 KB) |
|---|
| Author | J. R. Sites |
|---|
| Description | During the past quarter, we have achieved results in several areas as described below. In addition, Pamela Johnson successfully defended her PhD thesis, "The Effect of Trapping Defects on CIGS Solar-Cell Performance." She will spend June and July preparing part of that work for journal publication. Two students, Alan Davies and Jun Pan, who have just completed their first year of coursework, have joined the research group. |
|---|
| Venue | |
|---|
| Source | Colorado School of Mines, Golden, CO |
|---|
| Document Type | Quarterly Report (Word document) |
|---|
| Resource Date | 06/09/2003 |
|---|
|
| Post Date | 02/08/2005 |
|---|
| Title | QUARTERLY REPORT VII (MARCH - MAY 2003) |
|---|
| Link | (MS Word 27 KB) |
|---|
| Author | J. R. Sites |
|---|
| Description | Measurement and analysis. |
|---|
| Venue | Subcontract ADJ-1-30630-06 |
|---|
| Source | Colorado State University |
|---|
| Document Type | Quarterly Report (Word document) |
|---|
| Resource Date | 06/2003 |
|---|
|
| Post Date | 02/09/2005 |
|---|
| Title | THE FABRICATION AND PHYSICS OF HIGH-EFFICIENCY CADMIUM ? TELLURIDE THIN-FILM SOLAR CELLS |
|---|
| Link | (PDF 14 KB) Download Acrobat Reader. |
|---|
| Authors | A. Compaan, V. G. Karpov |
|---|
| Description | During this quarter, efforts continued on all three tasks: Cell Structure and Fabrication, Cell Modeling, and Characterization of Materials and Devices. In particular considerable emphasis was placed in Task 1 on the fabrication of CdS/CdTe cells in the substrate configuration as well as studies of grain boundary effects. In Task 2, much of the effort was placed on understanding the effects of buffer layers between TCO and CdS layers and their influence on stability and their relationship to back-contact doping. In Task 3, effort continued on the interpretation of x-ray fine structure data reported last quarter with ab initio FEFF analysis, AFM studies of superstrate and superstrate cells, and PL studies on ionimplanted crystalline CdTe and sputtered films before and after CdCl2 treatment. |
|---|
| Venue | NDJ-1-30630-02 Phase 3/Quarter 3 |
|---|
| Source | University of Toledo |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 06/2003 |
|---|
|
| Post Date | 02/08/2005 |
|---|
| Title | STUDIES OF BASIC ELECTRONIC PROPERTIES OF CDTE-BASED SOLAR CELLS & THEIR EVOLUTION DURING PROCESSING & STRESS |
|---|
| Link | (MS Word 4.6 MB) |
|---|
| Author | V. Kaydanov |
|---|
| Description | Analyze changes in AS data and EL patterns caused by cell stressing (cells were fabricated at First Solar). Also the STM images of CdS/CdTe/ZnTe:Cu structures are presented and discussed. |
|---|
| Venue | NREL quarterly |
|---|
| Source | Colorado School of Mines, Golden, CO |
|---|
| Document Type | Quarterly Report (Word document) |
|---|
| Resource Date | 05/2003 |
|---|
|
| Post Date | 02/09/2005 |
|---|
| Title | ADVANCED PROCESSING OF CDTE- AND CUINXGA1-XSE2- |
|---|
| Link | (PDF 234 KB) Download Acrobat Reader. |
|---|
| Authors | C. S. Ferekides, D. Morel |
|---|
| Description | The focus areas include: (a) CdTe ? stability, novel back/front contacts, and the development of manufacturing friendly processes; (b) CIGS ? development of two-step non-co-evaporation technology. |
|---|
| Venue | NDJ-2-30630-18 Phase II/Quarter I |
|---|
| Source | University of South Florida, Tampa |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 04/2003 |
|---|
|
| Post Date | 02/16/2005 |
|---|
| Title | QUARTERLY REPORT VI (DECEMBER 2002-FEBRUARY 2003) SUBCONTRACT ADJ-1-30630-06 |
|---|
| Link | (MS Word 37 KB) |
|---|
| Author | J. R. Sites |
|---|
| Description | |
|---|
| Venue | |
|---|
| Source | Colorado State University |
|---|
| Document Type | Quarterly Report (Word document) |
|---|
| Resource Date | 03/05/2003 |
|---|
|
| Post Date | 03/03/2005 |
|---|
| Title | STABILITY MECHANISMS IN THIN FILM CDTE SOLAR CELLS |
|---|
| Link | (MS Word 58 KB) |
|---|
| Author | L. Olsen |
|---|
| Description | Efforts concentrated on working with SSI to initiate accelerated testing of SSI circuits with and without barrier layer coatings. Details of the approach and some early results are discussed below. |
|---|
| Venue | 2nd Quarterly Report - Phase I: December 1, 2002 — February 28, 2003 |
|---|
| Source | Pacific Northwest National Lab (PNNL) |
|---|
| Document Type | Quarterly Report (Word document) |
|---|
| Resource Date | 03/2003 |
|---|
|
| Post Date | 02/08/2005 |
|---|
| Title | QUARTERLY REPORT VI (DECEMBER 2002-FEBRUARY 2003) |
|---|
| Link | (MS Word 37 KB) |
|---|
| Author | J. R. Sites |
|---|
| Description | Measurement and analysis. |
|---|
| Venue | Subcontract ADJ-1-30630-06 |
|---|
| Source | Colorado State University |
|---|
| Document Type | Quarterly Report (Word document) |
|---|
| Resource Date | 03/2003 |
|---|
|
| Post Date | 02/10/2005 |
|---|
| Title | QUARTERLY REPORT FOR SUBCONTRACT NAT-1-30620-08 |
|---|
| Link | (PDF 239 KB) Download Acrobat Reader. |
|---|
| Authors | C. S. Ferekides, D. Morel |
|---|
| Description | CdSe and CdZnTe |
|---|
| Venue | |
|---|
| Source | University of South Florida, Tampa |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 02/2003 |
|---|
|
| Post Date | 02/08/2005 |
|---|
| Title | STUDIES OF BASIC ELECTRONIC PROPERTIES OF CDTE-BASED SOLAR CELLS & THEIR EVOLUTION DURING PROCESSING & STRESS |
|---|
| Link | (MS Word 5.6 MB) |
|---|
| Author | V. Kaydanov |
|---|
| Description | Development of both the CdTe deposition techniques and methods for studies of cell electronic and structural properties. The latter was accompanied with application of these methods for characterization of differently processed and stressed cells. |
|---|
| Venue | NREL quarterly ADJ-2-30630-05 |
|---|
| Source | Colorado School of Mines, Golden, CO |
|---|
| Document Type | Quarterly Report (Word document) |
|---|
| Resource Date | 02/2003 |
|---|
|
| Post Date | 02/09/2005 |
|---|
| Title | FABRICATION AND PHYSICS OF HIGH-EFFICIENCY CADMIUM-TELLURIDE THIN-FILM SOLAR CELLS |
|---|
| Link | (PDF 112 KB) Download Acrobat Reader. |
|---|
| Authors | A. Compaan, V. G. Karpov |
|---|
| Description | This quarter, efforts continued on cell fabrication utilizing both SnO2:F and ZnO:A1 as the TCO... |
|---|
| Venue | NDJ-1-30630-02 Phase 2 Q3 |
|---|
| Source | University of Toledo |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 2003 |
|---|
|
| Post Date | 02/14/2005 |
|---|
| Title | ADVANCED PROCESSING OF CDTE- AND CUINXGA1-XSE2- BASED SOLAR CELLS |
|---|
| Link | (MS Word 648 KB) |
|---|
| Authors | C. S. Ferekides, D. Morel |
|---|
| Description | The focus areas include: (a) CdTe ? stability, novel back/front contacts, and the development of manufacturing friendly processes; (b) CIGS ? development of two-step non-co-evaporation technology |
|---|
| Venue | NDJ-2-30630-18 |
|---|
| Source | University of South Florida, Tampa |
|---|
| Document Type | Quarterly Report (Word document) |
|---|
| Resource Date | 10/2002 |
|---|
|
| Post Date | 02/14/2005 |
|---|
| Title | ADVANCED PROCESSING OF CDTE- AND CUINXGA1-XSE2- BASED SOLAR CELLS |
|---|
| Link | (MS Word 96 KB) |
|---|
| Authors | C. S. Ferekides, D. Morel |
|---|
| Description | |
|---|
| Venue | Phase I/Quarter I NDJ-2-30630-18 |
|---|
| Source | University of South Florida, Tampa |
|---|
| Document Type | Quarterly Report (Word document) |
|---|
| Resource Date | 04/2002 |
|---|
|
| Post Date | 02/10/2005 |
|---|
| Title | THE FABRICATION AND PHYSICS OF HIGH-EFFICIENCY CADMIUM ? TELLURIDE THIN-FILM SOLAR CELLS |
|---|
| Link | (PDF 282 KB) Download Acrobat Reader. |
|---|
| Authors | A. Compaan, V. G. Karpov |
|---|
| Description | This report describes our activities and progress in understanding of the effects of nonuniformities in CdTe photovoltaics. This includes PL mapping, light soaking of artificially nonuniform devices, and theoretical modeling. In our study we used VTD devices by First Solar, LLC and magnetron sputtered devices made at UT. |
|---|
| Venue | NDJ-1-30630-02 |
|---|
| Source | University of Toledo |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 03/2002 |
|---|
|
| Post Date | 02/09/2005 |
|---|
| Title | FABRICATION AND PHYSICS OF HIGH-EFFICIENCY CADMIUM ? TELLURIDE THIN-FILM SOLAR CELLS |
|---|
| Link | (PDF 380 KB) Download Acrobat Reader. |
|---|
| Authors | A. Compaan, V. G. Karpov |
|---|
| Description | The report highlights our results in developing characterization techniques and related understanding aimed at (a) quantitatively describing the density of states (DOS) of the defects determining the parameters of solar cell junctions (admittance spectroscopy) and (b) studying lateral effects in thin-film photovoltaics, including micrononuniformities in PL mapping, TCO and/or buffer layer quality, and nonlocal responses to the laser beam. In our study we used VTD devices by First Solar, LLC and magnetron-sputtered devices made at UT. |
|---|
| Venue | NDJ-1-30630-02 Phase 1/Quarter 1 |
|---|
| Source | University of Toledo |
|---|
| Document Type | Quarterly Report (Adobe Postscript file) |
|---|
| Resource Date | 12/2001 |
|---|
|
Back to Top Press Releases, Articles, Pictures/Tables/Figures, Other Items
| Post Date | 09/07/2006 |
|---|
| Title | A ROAD MAP TO U.S. DECARBONIZATION |
|---|
| Link | shinnarco2 |
|---|
| Authors | R. Shinnar, F. Citro |
|---|
| Description | Today, 85% of the United States' energy mix comes from carbon-rich fossil fuels: oil, natural gas, and coal (1). With demand increasing worldwide, existing oil reserves could peak within 20 years (2), followed by natural gas and coal. Growing fuel use is increasing CO2 and CH4 emissions and the risk of global warming. The United States has responded by sponsoring research into alternative energy (3). However, because research success is not predictable, an effective plan must be based on proven technologies. We propose to switch our economy slowly (over 30 to 50 or more years) to nonfossil energy sources by using proven technologies and available, expandable distribution systems. |
|---|
| Venue | Science 1 September 2006:Vol. 313. no. 5791, pp. 1243 - 1244DOI: 10.1126/science.1130338 |
|---|
| Source | Science |
|---|
| Document Type | Article (Hypertext link) |
|---|
| Resource Date | 09/01/2006 |
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|
| Post Date | 08/25/2006 |
|---|
| Title | FIRST SOLAR CDTE 100 MW GERMAN MANUFACTURING |
|---|
| Link | (MS Word 30 KB) |
|---|
| Author | N/A |
|---|
| Description | First Solar, a Phoenix, Ariz.-based company, has said it will invest nearly $150 million in a new solar module manufacturing plant in eastern Germany, a region that desperately needs the 400 jobs it is expected will be created.First Solar will build the plant in Frankfurt/Oder, a city of roughly 65,000 in Brandenburg, the eastern German state surrounding Berlin. The company aims to produce state-of-the-art thin film solar cells, which are substantially lighter than normal solar cells but produce the same or higher electrical currents.Upon completion, the plant will generate some 100 megawatts, the company said.The importance of the project for the city, and for the entire state, became clear at the contract`s official signing ceremony: Present were not only state Economy Minister Ulrich Junghans, of Chancellor Angela Merkel`s Christian Democratic Union, but also Wolfgang Tiefensee, the federal minister responsible for the reconstruction of eastern Germany. |
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| Venue | UPI story |
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| Source | UPI |
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| Document Type | Article (Word document) |
|---|
| Resource Date | 08/24/2006 |
|---|
|
| Post Date | 05/30/2006 |
|---|
| Title | PHONIX SONNENSTROM MODULE SUPPLY |
|---|
| Link | (MS Word 25 KB) |
|---|
| Author | N/A |
|---|
| Description | Phonix SonnenStrom AG has concluded a framework agreement with one of its existing suppliers for the long-term supply of solar modules. The purpose of the agreement is to supply thin film modules over the period from 2006 to 2011 with a guaranteed peak power of at least 158 MW. Stories at Solarbuzz: http://www.solarbuzz.com/news/NewsEUCO275.htm> and enf.cn: http://www.enf.cn/news/060530/1816.html> Phonix SonnenStrom: http://www.sonnenstromag.de/> |
|---|
| Venue | NCPV Hotline |
|---|
| Source | Phonix SonnenStrom AG |
|---|
| Document Type | Article (Word document) |
|---|
| Resource Date | 05/30/2006 |
|---|
|
| Post Date | 05/02/2006 |
|---|
| Title | DIMBACH, GERMANY: BECK ENERGY STARTS CONSTRUCTION OF WORLD'S LARGEST THIN FILM PROJECT |
|---|
| Link | fs_beck |
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| Author | N/A |
|---|
| Description | German PV system integrator, Beck Energy has started construction of the world's largest solar power system utilizing thin-film technology. Dimbach based, Beck Energy GmbH, a company that specializes in the development and construction of large-scale solar power plants has begun construction of the solar park "Markt Bibart I" in Markt Bibart (in the Neustadt Aisch administrative district) in co-operation with Bos.ten AG from Regensburg. When completed, the final output capacity will be 3.16 Megawatts, which is enough electricity to power about 1000 private homes. Bernhard Beck, CEO of Beck Energy and Michael Drysch, CEO of Bos.ten both took part in the ground-breaking ceremony for what will be the world's largest solar power plant utilizing crystalline thin-film technology. The electricity from the facility will be fed into the power grid of utility provider N-Ergie AG. The whole solar power plant will be fitted with Blitzstrom CTS modules manufactured by First Solar, their most significant features being high efficiency, cost effectiveness and a comprehensive end-of-life recycling management. Since June 2005, First Solar is offering to take back modules after their service life for recycling. They will then be reprocessed and the materials re-introduced into the production cycle. Beck Energy says that this life cycle management demonstrates the leading role of First Solar in the PV industry when it comes to maximizing the environmental benefits of solar technology. Beck Energy explains that it works in close co-operation with First Solar and favors CTS technology for large-scale solar power plants. |
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| Venue | Solarbuzz |
|---|
| Source | Solarbuzz |
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| Document Type | Article (Hypertext link) |
|---|
| Resource Date | 05/02/2006 |
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|
| Post Date | 04/27/2006 |
|---|
| Title | EU COMMISSION ENDORSES ?45 MILLION AID TO FIRST SOLAR FOR SOLAR MODULES PLANT IN GERMANY |
|---|
| Link | fs_europe_100mw |
|---|
| Author | N/A |
|---|
| Description | Brussels, 27th April 2006
State aid:The European Commission has authorised, under EC Treaty state aid rules, a ?45.5 million aid which the German Government plans to provide to FIRST SOLAR Manufacturing GmbH (FSM) for the creation of a plant for the manufacture of solar modules in Frankfurt (Oder), region of Brandenburg. The total cost of the investment will amount to some ?115 million. The Commission concluded that the aid was in line with the rules on regional investment aid and aid to small and medium sized enterprises (SMEs).
Competition Commissioner Neelie Kroes commented: ?I am pleased to endorse the aid for this investment project after an investigation lasting only four months, thanks to the quality of the notification and excellent cooperation from the German authorities?.
FSM was founded in 2005 and is owned by First Solar Holdings LLC, a predominantly US group of companies. FSM will install a solar module manufacturing plant with a nominal capacity of 100 MWp in Frankfurt (Oder). The company?s objective is to transfer and adapt its know-how and production techniques to the plant in order to begin producing solar modules in Europe?s fast growing market. FSM will use an alternative process to manufacture its solar modules - thin film photovoltaic technology - which requires only small amounts of raw materials and consumes little energy.
The investment will contribute to the development of the region of Brandenburg, in particular through the creation of a significant number of new jobs, thereby helping to alleviate the serious problem of unemployment in the region.
On the basis of Article 87(3) of the EC Treaty, state aid granted to promote the economic development of certain disadvantaged areas within the European Union may be considered compatible with the Single Market. Moreover, the beneficiary is a medium-sized enterprise under the EC definition of SMEs and is entitled to receive higher amounts of aid than large firms.
The Commission considered the aid to be compatible with the rules on regional aid to large investment projects and with the rules on aid to SMEs.
|
|---|
| Venue | website |
|---|
| Source | European Commission |
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| Document Type | Article (Hypertext link) |
|---|
| Resource Date | 04/27/2006 |
|---|
|
| Post Date | 04/10/2006 |
|---|
| Title | HAMBURG, GERMANY: REINECKE + POHL SUN ENERGY AG FINALIZES MODULE SUPPLY CONTRACT WITH FIRST SOLAR |
|---|
| Link | reineckeandpohl_fs_contract |
|---|
| Author | N/A |
|---|
| Description | German system integrator, Reinecke + Pohl Sun Energy AG has finalized a comprehensive contract to succeed the original agreement with First Solar, a United States solar module producer, with regard to long-term deliveries of thin-film modules. Based on the existing contracts, the allocation of major module components has been agreed upon until the year 2011. Already in the past year, the two companies signed a contract for a total of 20.2 MW modules, covering the period of 2005 to 2007. With this new important master agreement, Reinecke + Pohl Sun Energy AG is one of the leading purchasers of First Solar solar modules in Europe. The contract allows Reinecke + Pohl Sun Energy AG to increase its leading position as a system integrator in the thin-film technology field. |
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| Venue | Solarbuzz |
|---|
| Source | Solarbuzz |
|---|
| Document Type | Article (Hypertext link) |
|---|
| Resource Date | 04/10/2006 |
|---|
|
| Post Date | 05/02/2006 |
|---|
| Title | CLOSING THE LOOP ON CADMIUM |
|---|
| Link | (PDF 347 KB) Download Acrobat Reader. |
|---|
| Author | T. R. Hawkins |
|---|
| Description | In this study, the major flows of cadmium in the U.S. economy are quantified and the primary sinks are identified to gauge the need for additional policy to minimize the potential human health and ecosystem risks associated with these flows. Because of the concurrent occurrence of cadmium and zinc in ore, we also consider the relevant portions of the material cycle of zinc. |
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| Venue | ecomed publishers (Verlagsgruppe Hüthig Jehle Rehm GmbH), D-86899 Landsberg and Tokyo ? Mumbai ? Seoul ? Melbourne ? Paris Int J LCA 11 (1) 38 ? 48 (2006) |
|---|
| Source | Green Design Institute |
|---|
| Document Type | Article (Adobe Postscript file) |
|---|
| Resource Date | 2006 |
|---|
|
| Post Date | 01/16/2006 |
|---|
| Title | INTERVIEW WITH PHÖNIX SONNENSTROM AG CEO, DR. ANDREAS HÄNEL |
|---|
| Link | (MS Word 32 KB) |
|---|
| Author | P. Mints |
|---|
| Description | In 2003, Phönix SonnenStrom made the controversial decision to commit to thin films for a percentage of its future installations. With silicon's share of total shipments at approximately 95%, and with total thin film capacity at 78.9-MWp (8% of all available run-rate capacity), at the time it was a bold move. Times change, and the company's decision to include a higher percentage of thin films in its product mix now seems prescient. Silicon feedstock is now in short supply and will remain so for the near (or long) term, while on the spot market prices per kilogram are nearing $100.00. The raw material shortage is slowing overall industry growth, along with stalling growth for individual manufacturers and their customers, (system integrators, module assemblers, installers, etc.). Dr. Andreas Hänel, CEO of Phönix, agreed to talk to Solar Outlook about the company's commitment to thin films. |
|---|
| Venue | Solar Outlook Issue 2006-2 |
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| Source | Solar Outlook |
|---|
| Document Type | Article (Word document) |
|---|
| Resource Date | 01/2006 |
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|
| Post Date | 12/05/2005 |
|---|
| Title | UT PROFESSOR FINDS HIS PLACE IN THE SUNHOME'S DESIGN EARNS ENERGY-EFFICIENT AWARD |
|---|
| Link | compaan |
|---|
| Author | T. Henry |
|---|
| Description | Professor Compaan's ability to build an energy-efficient house was buoyed by the fact he's one of Ohio's top solar power researchers. His principal research focus, supported by the U.S. Department of Energy's National Renewable Energy Laboratory, is on advancing the development of thin films for solar cells. Those panels are the kind made and sold worldwide by First Solar LLC, a solar panel manufacturer in Arizona with a satellite plant in Perrysburg Township. |
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| Venue | Toledo Blade |
|---|
| Source | University of Toledo |
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| Document Type | Article (Hypertext link) |
|---|
| Resource Date | 12/05/2005 |
|---|
|
| Post Date | 11/17/2005 |
|---|
| Title | HOW THE PV INDUSTRY IS TO MINIMIZING THE HAZARDS OF SOLAR CELL MANUFACTURE |
|---|
| Link | fthenakisarticle2005november |
|---|
| Author | A. Cameron |
|---|
| Description | As PV manufacturing looks to make the step up from megawatt to gigawatt production, environmental issues arising from the manufacture and construction of solar cells need to be tackled head on in order to ensure that photovoltaic power can continue to represent itself as a green technology. Alasdair Cameron examines some of the issues. |
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| Venue | Renewable Energy World |
|---|
| Source | Renewable Energy World |
|---|
| Document Type | Article (Hypertext link) |
|---|
| Resource Date | 11/17/2005 |
|---|
|
| Post Date | 11/04/2005 |
|---|
| Title | SULZEMOOS, GERMANY: PHÖNIX SONNENSTROM AG SECURES ONE MEGAWATT CONTRACT |
|---|
| Link | firstsolar2005array |
|---|
| Author | N/A |
|---|
| Description | Having already closed a contract in mid-October for the construction of a green field photovoltaic plant using US based, First Solar's thin film modules, Phönix SonnenStrom AG received another order last week from mfs mainfrankenSolar 4 GmbH & Co. KG, a company based in Veitshoechheim, Germany, for a major plant with this module type. |
|---|
| Venue | Solar Buzz
|
|---|
| Sources | First Solar, Toledo, OH; Phonix SonnenStrom AG; Solarbuzz |
|---|
| Document Type | Article (Hypertext link) |
|---|
| Resource Date | 11/03/2005 |
|---|
|
| Post Date | 10/31/2005 |
|---|
| Title | SLIM AND STURDY SOLAR CELLS: NANOCRYSTALS OFFER PATH TO ELECTRICITY |
|---|
| Link | (MS Word 32 KB) |
|---|
| Author | A. Cunningham |
|---|
| Description | Engineers have for years been developing solar cells made of inexpensive plastic, but the devices have limitations. For instance, the cells' short lifetimes when exposed to sunlight have prevented these inventions from getting beyond the prototype phase. Now, researchers describe a solar cell made of thin films of inorganic CdTe nanocrystals that have several of the advantages of plastic but avoid some of its shortcomings. |
|---|
| Venue | Week of Oct. 22, 2005; Vol. 168, No. 17 |
|---|
| Source | Science News |
|---|
| Document Type | Article (Word document) |
|---|
| Resource Date | 10/22/2005 |
|---|
|
| Post Date | 08/25/2005 |
|---|
| Title | CSU RESEARCH TEAM FLIPS SWITCH ON BRIGHT IDEA |
|---|
| Link | (MS Word 42 KB) |
|---|
| Author | T. Hacker |
|---|
| Description | Now on the verge of a high-volume, low-cost production program, AVA Technologies LLC - the CdTe company formed by Sampath and research associates Kurt Barth and Al Enzenroth - is getting lots of attention. |
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| Venue | Northern Colorado Business Report |
|---|
| Sources | AVA Technologies; Colorado State University |
|---|
| Document Type | Article (Word document) |
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| Resource Date | 08/19/2005 |
|---|
|
| Post Date | 02/01/2006 |
|---|
| Title | UNDERSTANDING THE BENEFICIAL ROLE OF GRAIN BOUNDARIES IN POLYCRYSTALLINE SOLAR CELLS FROM SINGLE-GRAIN-BOUNDARY SCANNING PROBE MICROSCOPY |
|---|
| Link | (MS Word 24 KB) |
|---|
| Author | I. Visoly-Fisher |
|---|
| Description | The superior performance of certain polycrystalline (PX) solar cells compared to that of corresponding single-crystal ones has been an enigma until recently. Conventional knowledge predicted that grain boundaries serve as traps and recombination centers for the photogenerated carriers, which should decrease cell performance. To understand if cell performance is limited by grain bulk, grain surface, and/or grain boundaries (GBs), we performed high-resolution mapping of electronic properties of single GBs and grain surfaces in PX p-CdTe/n-CdS solar cells. Combining results from scanning electron and scanning probe microscopies, viz., capacitance, Kelvin probe, and conductive probe atomic force microscopies, and comparing images taken under varying conditions, allowed elimination of topography-related artifacts and verification of the measured properties. Our experimental results led to several interesting conclusions: 1) current is depleted near GBs, while photocurrents are enhanced along the GB cores; 2) GB cores are inverted, which explains GB core conduction. Conclusions (1) and (2) imply that the regions around the GBs function as an extension of the carrier-collection volume, i.e., they participate actively in the photovoltaic conversion process, while conclusion (2) implies minimal recombination at the GB cores; 3) the surface potential is diminished near the GBs; and 4) the photovoltaic and metallurgical junction in the n-CdS/p-CdTe devices coincide. These conclusions, taken together with gettering of defects and impurities from the bulk into the GBs, explain the good photovoltaic performance of these PX cells (at the expense of some voltage loss, as is indeed observed). We show that these CdTe GB features are induced by the CdCl2 heat treatment used to optimize these cells in the production process. |
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| Venue | http://www3.interscience.wiley.com/cgi-bin/abstract/112391774/ABSTRACT?CRETRY=1&SRETRY=0 |
|---|
| Source | Weizmann Institute |
|---|
| Document Type | Article (Word document) |
|---|
| Resource Date | 2005 |
|---|
|
| Post Date | 02/11/2005 |
|---|
| Title | ENVIRONMENTAL, HEALTH, AND SAFETY ISSUES IN PHOTOVOLTAIC TECHNOLOGIES: A SUMMARY (DRAFT) |
|---|
| Link | (MS Word 40 KB) |
|---|
| Author | V. Fthenakis |
|---|
| Description | As with any energy source or product, there are environmental, health and safety (EHS) hazards associated with the manufacture, use, and disposal of solar cells. Although the PV industry uses far smaller amounts of toxic- and flammable-substances than many other industries, its use of hazardous chemicals can entail occupational and environmental hazards. Addressing EHS concerns is the focus of numerous studies at Brookhaven National Laboratory, under the auspices of the US Department of Energy's National Photovoltaic Program. More than 150 articles highlighting these studies are posted in our bibliography. Below is a summary of EHS issues pertaining to the manufacture of crystalline-Si, amorphous silicon, CuInSe2 and CdTe solar cells. We will promptly send the full articles to the reader who wants more details. |
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| Venue | draft |
|---|
| Source | Brookhaven National Laboratory |
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| Document Type | Article (Word document) |
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| Resource Date | 2004 |
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|
| Post Date | 02/11/2005 |
|---|
| Title | OVERVIEW OF POTENTIAL PV HAZARDS |
|---|
| Link | (PDF 136 KB) Download Acrobat Reader. |
|---|
| Author | V. Fthenakis |
|---|
| Description | The PV industry uses toxic and flammable substances, although in smaller amounts than many other industries, and use of hazardous chemicals can involve occupational and environmental hazards. Addressing EHS concerns is the focus of numerous studies of the National Photovoltaic EHS Assistance Center at Brookhaven National Laboratory, which operates under the auspices of the US Department of Energy (DOE). More than 150 articles highlighting these studies are posted in the Center's website (http:// www.pv.bnl.gov). This work has been done in cooperation with the US DOE PV Program and the US PV industry, which takes EHS issues very seriously and reacts proactively to concerns. Below is a summary of EHS issues pertaining to the manufacture of crystalline silicon (x-Si), amorphous silicon (a-Si), copper indium diselenide (CIS), copper indium gallium diselenide (CGS), gallium arsenide (GaAs) and cadmium telluride (CdTe), which are currently commercially available. |
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| Venue | Practical Handbook of Photovoltaics: Fundamentals and Applications |
|---|
| Source | Brookhaven National Laboratory |
|---|
| Document Type | Article (Adobe Postscript file) |
|---|
| Resource Date | 2004 |
|---|
|
| Post Date | 02/04/2005 |
|---|
| Title | ANTEC SOLAR RESTARTS CDTE MODULE PRODUCTION |
|---|
| Link | Antec Solar restarts CdTe module production |
|---|
| Author | J. Siemer |
|---|
| Description | Production at Antec Solar's factory in Arnstadt, Germany was relaunched in mid-May, following Frankfurt-based Ökologik Ecovest AG's acquisition of the rest of the insolvent module manufacturer. Ecovest itself is one of the biggest buyers of the factory's CdTe product. |
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| Venue | Photon International |
|---|
| Source | Antec Solar |
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| Document Type | Article (Hypertext link) |
|---|
| Resource Date | 07/2003 |
|---|
|
| Post Date | 08/14/2006 |
|---|
| Title | HIGH-THROUGHPUT VACUUM PROCESSING
FOR INNOVATIVE USES OF GLASS |
|---|
| Link | (PDF 965 KB) Download Acrobat Reader. |
|---|
| Author | K. L. Barth |
|---|
| Description | The high-throughput technology seeks to fill the PV industry?s critical need to meet the 25% annual increase in manufacturing demand for PV. The process produces thin-film CdTe glass substrates that have the highest longterm potential for low-cost fabrication of solar cells. AVA and heated-pocket deposition technologies present many marketing opportunities for a broad range of products, including many that use glass substrates. |
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| Venue | OFFICE OF INDUSTRIAL TECHNOLOGIES ENERGY EFFICIENCY AND RENEWABLE ENERGY ? U.S. DEPARTMENT OF ENergy Order# I-GL-820 |
|---|
| Source | US DOE |
|---|
| Document Type | Article (Adobe Postscript file) |
|---|
| Resource Date | 09/2001 |
|---|
|
| Post Date | 02/10/2005 |
|---|
| Title | TELLURIUM |
|---|
| Link | (PDF 54 KB) Download Acrobat Reader. |
|---|
| Author | R. D. Brown |
|---|
| Description | Tellurium is a relatively rare element, tied for 71st place although they are often referred to as metals when in with platinum and palladium in rank of crustal abundance. It elemental form. Tellurium was first identified in 1782 in is in the same chemical family as oxygen, sulfur, selenium, Transylvanian gold ore (Azimov, 1994, p. 260). For more and polonium: oxygen and sulfur are nonmetals, polonium is than a century, tellurium was an experimental material having a metal, and selenium and tellurium are semiconductors... |
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| Venue | USGS |
|---|
| Source | US Dept Interior |
|---|
| Document Type | Article (Adobe Postscript file) |
|---|
| Resource Date | 1999 |
|---|
|
| Post Date | 10/26/2006 |
|---|
| Title | FIRST SOLAR S-1 IPO REGISTRATION STATEMENT |
|---|
| Link | firstsolar_ipo_profitable_quarter |
|---|
| Author | N/A |
|---|
| Description | History, status, and future of First Solar, including profitable Sept 06 Q |
|---|
| Venue | SEC |
|---|
| Source | First Solar, Toledo, OH |
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| Document Type | Other Items (Hypertext link) |
|---|
| Resource Date | 10/26/2006 |
|---|
|
| Post Date | 07/03/2006 |
|---|
| Title | FIRST SOLAR IPO REGISTRATION |
|---|
| Link | (MS Word 25 KB) |
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| Author | N/A |
|---|
| Description | First Solar Inc. filed to raise up to $250 million in its initial public offering. Press at: http://www.marketwatch.com/News/Story/Story.aspx?guid=%7BD0413290%2D2944%2D407E%2D9DE7%2D60A64B9914F7%7D&siteid=mktw&dist=nbk> or http://tinyurl.com/hgctv> Additional Press: http://www.reed-electronics.com/electronicnews/article/CA6349250.html> or http://tinyurl.com/lfqml> http://www.eetimes.com/news/semi/showArticle.jhtml?articleID=190100018> or http://tinyurl.com/rbxx3> First Solar: http://www.firstsolar.com/> |
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| Venue | |
|---|
| Source | First Solar, Toledo, OH |
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| Document Type | Other Items (Word document) |
|---|
| Resource Date | 06/03/2006 |
|---|
|
| Post Date | 03/22/2006 |
|---|
| Title | SOLARPACT WEBSITE |
|---|
| Link | solarpact_bonnet_website |
|---|
| Author | D. Bonnet |
|---|
| Description | International organization of scientists working in CdTe PV |
|---|
| Venue | website |
|---|
| Source | SolarPact |
|---|
| Document Type | Other Items (Hypertext link) |
|---|
| Resource Date | 03/2006 |
|---|
|
| Post Date | 11/11/2005 |
|---|
| Title | POLYCRYSTALLINE THIN FILM DEVICE DEGRADATION STUDIES |
|---|
| Link | (PowerPoint 4.7 MB) |
|---|
| Author | D. Albin |
|---|
| Description | stress testing CIS and CdTe cells. |
|---|
| Venue | DOE Solar Review Meeting 2005 |
|---|
| Source | National Renewable Energy Laboratory |
|---|
| Document Type | Other Items (Powerpoint presentation) |
|---|
| Resource Date | 11/2005 |
|---|
|
| Post Date | 06/14/2005 |
|---|
| Title | COLORADO STATE UNIVERSITY, PROFESSOR JIM SITES, LINKS TO COLLECTED PAPERS |
|---|
| Link | SitesCSUwebsitePapers |
|---|
| Author | J. R. Sites |
|---|
| Description | Website URL for CSU thin film PV papers |
|---|
| Venue | Website |
|---|
| Source | Colorado State University |
|---|
| Document Type | Other Items (Hypertext link) |
|---|
| Resource Date | 06/2005 |
|---|
|
| Post Date | 05/16/2005 |
|---|
| Title | CDTE CELLS: HAVE WE HIT THE WALL? |
|---|
| Link | (MS Word 29 KB) |
|---|
| Authors | M. Gloeckler, J. R. Sites |
|---|
| Description | Bolko's e-mail from Wednesday raises the issue of whether we can expect the efficiency to go much higher than 16.5% with CdTe. He makes several observations and suggestions, with the implication that significant progress will likely require more outside-the-box thinking. We will give our observations and suggestions below. Some of them overlap with Bolko?s, but more importantly, we agree that major efficiency improvements will likely require more radical approaches. |
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| Venue | e-mail attachment |
|---|
| Source | Colorado State University |
|---|
| Document Type | Other Items (Word document) |
|---|
| Resource Date | 05/16/2005 |
|---|
|
| Post Date | 02/08/2005 |
|---|
| Title | LETTER FROM NATIONAL STARCH TO CSU |
|---|
| Link | (MS Word 27 KB) |
|---|
| Author | D. E. Miles |
|---|
| Description | Commitment to pursue CdTe technology. |
|---|
| Venue | Kurt Barth |
|---|
| Source | Colorado State University |
|---|
| Document Type | Other Items (Word document) |
|---|
| Resource Date | 04/08/2004 |
|---|
|
| Post Date | 02/08/2005 |
|---|
| Title | FACTORS AFFECTING THE STABILITY OF CDTE/CDS SOLAR CELLS, DEDUCED FROM STRESS TESTS AT ELEVATED TEMPERATURE |
|---|
| Link | (PDF 225 KB) Download Acrobat Reader. |
|---|
| Authors | I. Visoly-Fisher, et al. |
|---|
| Description | The stability of CdTe/CdS solar cells appears to be dictated by two distinct mechanisms, viz. excess Cu in CdS, which degrades the photovoltaic junction, and O 2/H2O ? induced formation of an insulating oxide at the CdTe back surface contact, creating a barrier for hole transport. This understanding helps to get cells, also Cu containing ones, that are a priori stable or show self-repair, as shown experimentally. |
|---|
| Venue | |
|---|
| Source | Weizmann Institute |
|---|
| Document Type | Other Items (Adobe Postscript file) |
|---|
| Resource Date | 2003 |
|---|
|
| Post Date | 07/25/2006 |
|---|
| Title | CONTACT INFORMATION FOR US THIN FILM COMPANIES |
|---|
| Link | (MS Word 37 KB) |
|---|
| Author | K. Zweibel |
|---|
| Description | Names, materials, phone numbers, emails |
|---|
| Venue | |
|---|
| Source | National Renewable Energy Laboratory |
|---|
| Document Type | Picture/Table/Figure (Word document) |
|---|
| Resource Date | 07/25/2006 |
|---|
|
| Post Date | 06/14/2006 |
|---|
| Title | SOME NOTES FROM CDTE WORKSHOP FOLLOWING 2006 EMRS MEETING NICE/FREJUS, FRANCE, JUNE 2-3, 2006 |
|---|
| Link | (MS Word 31 KB) |
|---|
| Author | T. Gessert |
|---|
| Description | The CdTe/Solarpact Workshop took place following the 2006 EMRS Meeting at two locations: At Acropolis Congress Center (Nice, June 6, ~1.5-hr session immediately following the EMRS meeting), and at the La Villa Clythia (Frejus, June 7, In conjunction with CIGS Workshop). The session in Nice included prepared presentations related to the topic of ?Limitations and Challenges for CdTe Thin-Film Solar Cells.? Some presentation highlights follow. Discussion in Frejus was less structured but produced some lively moments related to technical and political challenges facing world-wide commercialization of CdTe-based thin film devices. |
|---|
| Venue | 2006 EMRS MeetingNice/Frejus, France, June 2-3, 2006, |
|---|
| Source | National Renewable Energy Laboratory |
|---|
| Document Type | Picture/Table/Figure (Word document) |
|---|
| Resource Date | 06/2006 |
|---|
|
| Post Date | 03/20/2006 |
|---|
| Title | MODULE PERFORMANCE TAKEN FROM COMPANY WEBSITES |
|---|
| Link | (MS Word 28 KB) |
|---|
| Author | B. Von Roedern |
|---|
| Description | Efficiency, power, temperature coefficients of PV modules |
|---|
| Venue | website data |
|---|
| Source | National Renewable Energy Laboratory |
|---|
| Document Type | Picture/Table/Figure (Word document) |
|---|
| Resource Date | 03/2006 |
|---|
|
| Post Date | 03/09/2006 |
|---|
| Title | FIRST SOLAR MAJOR CDTE PROJECTS 2005 |
|---|
| Link | (PowerPoint 1.7 MB) |
|---|
| Author | P. Vaughnn |
|---|
| Description | Pictures, locations, short descriptions of 10 MWp of projects, mostly in Germany |
|---|
| Venue | Photos and text, with permission |
|---|
| Source | N/A |
|---|
| Document Type | Picture/Table/Figure (Powerpoint presentation) |
|---|
| Resource Date | 03/2006 |
|---|
|
| Post Date | 02/24/2006 |
|---|
| Title | MODULE RATINGS FROM WEBSITES |
|---|
| Link | (MS Word 44 KB) |
|---|
| Author | B. Von Roedern |
|---|
| Description | Total area efficiencies of available modules |
|---|
| Venue | |
|---|
| Source | National Renewable Energy Laboratory |
|---|
| Document Type | Picture/Table/Figure (Word document) |
|---|
| Resource Date | 02/2006 |
|---|
|
| Post Date | 01/05/2006 |
|---|
| Title | SPEC-SHEET RATINGS FROM MANUFACTURERS WEBSITES |
|---|
| Link | (MS Word 43 KB) |
|---|
| Author | B. Von Roedern |
|---|
| Description | Total Area module efficiencies, Companies, Names, descriptions, temperature coefficients |
|---|
| Venue | |
|---|
| Source | National Renewable Energy Laboratory |
|---|
| Document Type | Picture/Table/Figure (Word document) |
|---|
| Resource Date | 01/2006 |
|---|
|
| Post Date | 11/04/2005 |
|---|
| Title | THIN FILM TECHNOLOGY |
|---|
| Link | (PDF 2.2 MB) Download Acrobat Reader. |
|---|
| Author | K. Zweibel |
|---|
| Description | Display developed to show thin film activities to NREL visitors |
|---|
| Venue | Display |
|---|
| Source | National Renewable Energy Laboratory |
|---|
| Document Type | Picture/Table/Figure (Adobe Postscript file) |
|---|
| Resource Date | 11/2005 |
|---|
|
| Post Date | 11/17/2005 |
|---|
| Title | SPUTTERED II-VI ALLOYS AND STRUCTURES FOR TANDEMS |
|---|
| Link | (PowerPoint 568 KB) |
|---|
| Author | A. Compaan |
|---|
| Description | CdTe and tandems |
|---|
| Venue | Solar Review Meeting 2005 |
|---|
| Source | University of Toledo |
|---|
| Document Type | Picture/Table/Figure (Powerpoint presentation) |
|---|
| Resource Date | 11/2005 |
|---|
|
| Post Date | 11/17/2005 |
|---|
| Title | CHARACTERIZATION OF THE ELECTRONIC AND CHEMICAL STRUCTURE OF THIN FILM SOLAR CELL INTERFACES |
|---|
| Link | (PDF 152 KB) Download Acrobat Reader. |
|---|
| Author | C. Heske |
|---|
| Description | analysis of device and materials charateristics |
|---|
| Venue | DOE Solar Program Review 2005 |
|---|
| Source | University of Nevada, Las Vegas |
|---|
| Document Type | Picture/Table/Figure (Adobe Postscript file) |
|---|
| Resource Date | 11/2005 |
|---|
|
| Post Date | 11/17/2005 |
|---|
| Title | CU AND BUFFER LAYERS AFFECT ON CDTE STABILITY AND PERFORMANCE |
|---|
| Link | (JPG 1.4 MB) |
|---|
| Author | C. S. Ferekides |
|---|
| Description | CdTe stability and performance; copper, TCOs, buffer layers |
|---|
| Venue | DOE Solar Review 2005 |
|---|
| Source | University of South Florida, Tampa |
|---|
| Document Type | Picture/Table/Figure (JPG image) |
|---|
| Resource Date | 11/2005 |
|---|
|
| Post Date | 11/11/2005 |
|---|
| Title | DEEP ELECTRONIC STATES IN CDTE BY ADMITTANCE TECHNIQUES |
|---|
| Link | (PowerPoint 256 KB) |
|---|
| Author | F. H. Seymour |
|---|
| Description | examination of defects in CdTe cells |
|---|
| Venue | 2005 DOE Solar Review |
|---|
| Source | Colorado School of Mines, Golden, CO |
|---|
| Document Type | Picture/Table/Figure (Powerpoint presentation) |
|---|
| Resource Date | 11/2005 |
|---|
|
| Post Date | 11/11/2005 |
|---|
| Title | INTEGRATING DEPOSITION, PROCESSING, CHARACTERIZATION AT NREL |
|---|
| Link | (PowerPoint 2.7 MB) |
|---|
| Author | B. Nelson |
|---|
| Description | Machines designed to perform multiple tasks |
|---|
| Venue | DOE Solar Review 2005 |
|---|
| Source | National Renewable Energy Laboratory |
|---|
| Document Type | Picture/Table/Figure (Powerpoint presentation) |
|---|
| Resource Date | 11/2005 |
|---|
|
| Post Date | 11/29/2005 |
|---|
| Title | US THIN FILM COMPANY CONTACTS |
|---|
| Link | (MS Word 39 KB) |
|---|
| Author | K. Zweibel |
|---|
| Description | Companies, names, phone numbers, e-mails, websites, technology |
|---|
| Venue | |
|---|
| Source | National Renewable Energy Laboratory |
|---|
| Document Type | Picture/Table/Figure (Word document) |
|---|
| Resource Date | 11/2005 |
|---|
|
| Post Date | 10/31/2005 |
|---|
| Title | FIRST SOLAR CDTE ARRAYS IN GERMANY 2005 |
|---|
| Link | (PowerPoint 321 KB) |
|---|
| Author | P. Vaughnn |
|---|
| Description | Pictures of ground and roof mounted arrays |
|---|
| Venue | |
|---|
| Sources | Beck Energy, Germany; First Solar, Toledo, OH |
|---|
| Document Type | Picture/Table/Figure (Powerpoint presentation) |
|---|
| Resource Date | 10/2005 |
|---|
|
| Post Date | 11/01/2005 |
|---|
| Title | BEST LARGE AREA THIN FILM MODULE PROTOTYPES OCTOBER 2005 |
|---|
| Link | (MS Word 43 KB) |
|---|
| Author | K. Zweibel |
|---|
| Description | Ranked by power, all thin film technologies, up to date efficiencies, sizes, output. |
|---|
| Venue | |
|---|
| Source | National Renewable Energy Laboratory |
|---|
| Document Type | Picture/Table/Figure (Word document) |
|---|
| Resource Date | 10/2005 |
|---|
|
| Post Date | 08/15/2005 |
|---|
| Title | COMMERCIAL THIN FILM MODULES, DATA TAKEN FROM WEBSITES (TOTAL AREA EFFICIENCIES) |
|---|
| Link | (MS Word 34 KB) |
|---|
| Author | B. Von Roedern |
|---|
| Description | Efficiency, power, temperature coefficients, approximate price |
|---|
| Venue | |
|---|
| Source | National Renewable Energy Laboratory |
|---|
| Document Type | Picture/Table/Figure (Word document) |
|---|
| Resource Date | 08/2005 |
|---|
|
| Post Date | 07/01/2005 |
|---|
| Title | BEST RESEARCH CELL EFFICIENCIES |
|---|
| Link | (PowerPoint 1.2 MB) |
|---|
| Authors | L. Kazmerski, K. Zweibel |
|---|
| Description | Chronology of world record lab cell efficiencies, all technologies |
|---|
| Venue | |
|---|
| Source | National Renewable Energy Laboratory |
|---|
| Document Type | Picture/Table/Figure (Powerpoint presentation) |
|---|
| Resource Date | 06/2005 |
|---|
|
| Post Date | 05/09/2005 |
|---|
| Title | CDTE NATIONAL R&D TEAM |
|---|
| Link | (JPG 375 KB) |
|---|
| Author | K. Zweibel |
|---|
| Description | 50 scientific members of the Thin Film Partnship's CdTe National R&D Team at a meeting in Golden, CO, 5/5/05 |
|---|
| Venue | Team Meeting photo |
|---|
| Source | National Renewable Energy Laboratory |
|---|
| Document Type | Picture/Table/Figure (JPG image) |
|---|
| Resource Date | 05/05/2005 |
|---|
|
| Post Date | 05/20/2005 |
|---|
| Title | CDTE NATIONAL R&D TEAM MEETING MAY 2005: ATTENDANCE LIST |
|---|
| Link | (MS Word 108 KB) |
|---|
| Author | H. S. Ullal |
|---|
| Description | Names, e-mail, phone numbers |
|---|
| Venue | CdtE National R&D Team |
|---|
| Source | National Renewable Energy Laboratory |
|---|
| Document Type | Picture/Table/Figure (Word document) |
|---|
| Resource Date | 05/2005 |
|---|
|
| Post Date | 05/12/2005 |
|---|
| Title | SIMPLE DIAGRAMS OF THE DEVICE STRUCTURES OF CIS, A-SI, AND CDTE CELLS |
|---|
| Link | (PowerPoint 2.1 MB) |
|---|
| Author | D. Gwinner |
|---|
| Description | |
|---|
| Venue | |
|---|
| Source | National Renewable Energy Laboratory |
|---|
| Document Type | Picture/Table/Figure (Powerpoint presentation) |
|---|
| Resource Date | 05/2005 |
|---|
|
| Post Date | 04/05/2005 |
|---|
| Title | FIRST SOLAR 1.3 MWP PV ARRAY IN GERMANY |
|---|
| Link | (MS Word 74.4 MB) |
|---|
| Author | N/A |
|---|
| Description | photos |
|---|
| Venue | |
|---|
| Source | First Solar, Toledo, OH |
|---|
| Document Type | Picture/Table/Figure (Word document) |
|---|
| Resource Date | 2005 |
|---|
|
| Post Date | 02/08/2005 |
|---|
| Title | WORLD THIN FILM MODULE PRODUCTION ALMOST DOUBLED IN 2004 |
|---|
| Link | (Excel 28 KB) |
|---|
| Author | K. Zweibel |
|---|
| Description | World thin film module sales from Strategies Unlimited for 1981 to 2004. |
|---|
| Venue | Strategies Unlimited |
|---|
| Source | Strategies Unlimited |
|---|
| Document Type | Picture/Table/Figure (Excel spreadsheet) |
|---|
| Resource Date | 01/2005 |
|---|
|
| Post Date | 02/02/2005 |
|---|
| Title | BEST ONE OF A KIND THIN FILM PV LABORATORY CELLS (TO 2004) |
|---|
| Link | (JPG 60 KB) |
|---|
| Author | K. Zweibel |
|---|
| Description | chronology of cell efficiency improvements |
|---|
| Venue | |
|---|
| Source | National Renewable Energy Laboratory |
|---|
| Document Type | Picture/Table/Figure (JPG image) |
|---|
| Resource Date | 12/2004 |
|---|
|
| Post Date | 02/14/2005 |
|---|
| Title | FIRST SOLAR MONTHLY PERFORMANCE ANALYSIS |
|---|
| Link | (Excel 37 KB) |
|---|
| Author | N/A |
|---|
| Description | First Solar Performance Ratios on German systems |
|---|
| Venue | |
|---|
| Source | First Solar, Toledo, OH |
|---|
| Document Type | Picture/Table/Figure (Excel spreadsheet) |
|---|
| Resource Date | 12/2004 |
|---|
|
| Post Date | 02/07/2005 |
|---|
| Title | THIN FILM LEARNING CURVE (ESTIMATED) |
|---|
| Link | (PowerPoint 130 KB) |
|---|
| Author | K. Zweibel |
|---|
| Description | Staring a new learning curve for thin films. |
|---|
| Venue | |
|---|
| Source | National Renewable Energy Laboratory |
|---|
| Document Type | Picture/Table/Figure (Powerpoint presentation) |
|---|
| Resource Date | 10/2004 |
|---|
|
| Post Date | 02/15/2005 |
|---|
| Title | FIRST SOLAR MONTHLY PERFORMANCE ANALYSIS OF TUCSON ELECTRIC POWER ARRAY #4 (129 KW) TO AUGUST 2004 |
|---|
| Link | (Excel 48 KB) |
|---|
| Author | N/A |
|---|
| Description | Output and performance ratio |
|---|
| Venue | |
|---|
| Sources | First Solar, Toledo, OH; Tucson Electric |
|---|
| Document Type | Picture/Table/Figure (Excel spreadsheet) |
|---|
| Resource Date | 10/2004 |
|---|
|
| Post Date | 02/15/2005 |
|---|
| Title | FIRST SOLAR MONTHLY PERFORMANCE ANALYSIS OF TUCSON ELECTRIC POWER ARRAY #3 (126 KW) TO AUGUST 2004 |
|---|
| Link | (Excel 44 KB) |
|---|
| Author | N/A |
|---|
| Description | Energy output and performance ratio |
|---|
| Venue | |
|---|
| Sources | First Solar, Toledo, OH; Tucson Electric |
|---|
| Document Type | Picture/Table/Figure (Excel spreadsheet) |
|---|
| Resource Date | 09/2004 |
|---|
|
| Post Date | 02/02/2005 |
|---|
| Title | SPEC-SHEET RATINGS (FROM MANUFACTURER?S WEBSITES) |
|---|
| Link | (MS Word 23 KB) |
|---|
| Author | B. Von Roedern |
|---|
| Description | Commercial module ratings 2004 |
|---|
| Venue | |
|---|
| Source | National Renewable Energy Laboratory |
|---|
| Document Type | Picture/Table/Figure (Word document) |
|---|
| Resource Date | 08/2004 |
|---|
|
| Post Date | 02/07/2005 |
|---|
| Title | PROJECTED US THIN FILM GROWTH BY TECHNOLOGY 2002-2005 |
|---|
| Link | (PowerPoint 737 KB) |
|---|
| Author | K. Zweibel |
|---|
| Description | MWp of sales 2002-2005. |
|---|
| Venue | |
|---|
| Source | National Renewable Energy Laboratory |
|---|
| Document Type | Picture/Table/Figure (Powerpoint presentation) |
|---|
| Resource Date | 07/2004 |
|---|
|
| Post Date | 02/08/2005 |
|---|
| Title | FIRST SOLAR ARRAY IN GERMANY |
|---|
| Link | (JPG 605 KB) |
|---|
| Author | N/A |
|---|
| Description | |
|---|
| Venue | |
|---|
| Source | First Solar, Toledo, OH |
|---|
| Document Type | Picture/Table/Figure (JPG image) |
|---|
| Resource Date | 2004 |
|---|
|
| Post Date | 02/09/2005 |
|---|
| Title | FIRST SOLAR CDTE ARRAY IN GERMANY WITH SHEEP AND FARMER |
|---|
| Link | (JPG 1.1 MB) |
|---|
| Author | N/A |
|---|
| Description | |
|---|
| Venue | |
|---|
| Source | First Solar, Toledo, OH |
|---|
| Document Type | Picture/Table/Figure (JPG image) |
|---|
| Resource Date | 2004 |
|---|
|
| Post Date | 02/09/2005 |
|---|
| Title | FIRST SOLAR CDTE ARRAY IN GERMANY NEAR SUNDOWN |
|---|
| Link | (JPG 495 KB) |
|---|
| Author | N/A |
|---|
| Description | |
|---|
| Venue | |
|---|
| Sources | Beck Energy, Germany; First Solar, Toledo, OH |
|---|
| Document Type | Picture/Table/Figure (JPG image) |
|---|
| Resource Date | 2004 |
|---|
|
| Post Date | 02/09/2005 |
|---|
| Title | FIRST SOLAR CDTE ARRAY IN GERMANY CLOSE-UP |
|---|
| Link | (JPG 614 KB) |
|---|
| Author | N/A |
|---|
| Description | |
|---|
| Venue | |
|---|
| Source | First Solar, Toledo, OH |
|---|
| Document Type | Picture/Table/Figure (JPG image) |
|---|
| Resource Date | 2004 |
|---|
|
| Post Date | 02/09/2005 |
|---|
| Title | FIRST SOLAR CDTE ARRAY IN GERMANY WITH SUNFLOWERS |
|---|
| Link | (JPG 973 KB) |
|---|
| Author | N/A |
|---|
| Description | |
|---|
| Venue | |
|---|
| Source | First Solar, Toledo, OH |
|---|
| Document Type | Picture/Table/Figure (JPG image) |
|---|
| Resource Date | 2004 |
|---|
|
| Post Date | 02/09/2005 |
|---|
| Title | FIRST SOLAR CDTE ARRAY AT SPRINGERVILLE, AZ, TUCSON ELECTRIC |
|---|
| Link | (JPG 421 KB) |
|---|
| Author | K. Zweibel |
|---|
| Description | |
|---|
| Venue | |
|---|
| Sources | First Solar, Toledo, OH; Tucson Electric |
|---|
| Document Type | Picture/Table/Figure (JPG image) |
|---|
| Resource Date | 2004 |
|---|
|
| Post Date | 02/14/2005 |
|---|
| Title | FIRST SOLAR FIELDED ENERGY PERFORMANCE OVERVIEW 2004 |
|---|
| Link | (Excel 21 KB) |
|---|
| Author | N/A |
|---|
| Description | All systems |
|---|
| Venue | |
|---|
| Source | First Solar, Toledo, OH |
|---|
| Document Type | Picture/Table/Figure (Excel spreadsheet) |
|---|
| Resource Date | 2004 |
|---|
|
| Post Date | 02/10/2005 |
|---|
| Title | HALF A MW OF FIRST SOLAR CDTE AT TUCSON ELECTRIC |
|---|
| Link | (JPG 124 KB) |
|---|
| Author | K. Zweibel |
|---|
| Description | |
|---|
| Venue | |
|---|
| Source | First Solar, Toledo, OH |
|---|
| Document Type | Picture/Table/Figure (JPG image) |
|---|
| Resource Date | 2004 |
|---|
|
| Post Date | 02/10/2005 |
|---|
| Title | FIRST SOLAR CDTE ARRAY AT TUCSON ELECTRIC |
|---|
| Link | (JPG 110 KB) |
|---|
| Author | K. Zweibel |
|---|
| Description | |
|---|
| Venue | |
|---|
| Sources | First Solar, Toledo, OH; National Renewable Energy Laboratory; Tucson Electric |
|---|
| Document Type | Picture/Table/Figure (JPG image) |
|---|
| Resource Date | 2004 |
|---|
|
| Post Date | 02/10/2005 |
|---|
| Title | HALF A MW OF CDTE AT SPRINGERVILLE, AZ |
|---|
| Link | (JPG 392 KB) |
|---|
| Author | N/A |
|---|
| Description | |
|---|
| Venue | |
|---|
| Sources | National Renewable Energy Laboratory; Tucson Electric |
|---|
| Document Type | Picture/Table/Figure (JPG image) |
|---|
| Resource Date | 2004 |
|---|
|
| Post Date | 01/18/2004 |
|---|
| Title | BECK ENERGY PHOTO OF PART OF FIRST SOLAR CDTE ARRAY FIELD IN GERMANY |
|---|
| Link | (JPG 21 KB) |
|---|
| Author | None |
|---|
| Description | First Solar CdTe array in Germany. |
|---|
| Venue | |
|---|
| Sources | Beck Energy, Germany; First Solar, Toledo, OH |
|---|
| Document Type | Picture/Table/Figure (JPG image) |
|---|
| Resource Date | 2003 |
|---|
|
| Post Date | 02/04/2005 |
|---|
| Title | BEST RESEARCH CELL EFFICIENCIES |
|---|
| Link | (PowerPoint 586 KB) |
|---|
| Author | L. Kazmerski |
|---|
| Description | All technologies through 2003 |
|---|
| Venue | |
|---|
| Source | National Renewable Energy Laboratory |
|---|
| Document Type | Picture/Table/Figure (Powerpoint presentation) |
|---|
| Resource Date | 2003 |
|---|
|
| Post Date | 02/08/2005 |
|---|
| Title | 11% CDTE MODULE FROM BP SOLAR MEASURED AT NREL |
|---|
| Link | (MS Word 31 KB) |
|---|
| Author | D. Cunningham |
|---|
| Description | Then world record CdTe module verified at NREL 11% aperture area. |
|---|
| Venue | test report |
|---|
| Sources | BP Solar; National Renewable Energy Laboratory |
|---|
| Document Type | Picture/Table/Figure (Word document) |
|---|
| Resource Date | 12/19/2002 |
|---|
|
| Post Date | 02/08/2005 |
|---|
| Title | CADMIUM IN COAL |
|---|
| Link | (Excel 99 KB) |
|---|
| Author | V. Fthenakis |
|---|
| Description | EPRI summary of Cd in coal. |
|---|
| Venue | PISCES database |
|---|
| Source | EPRI |
|---|
| Document Type | Picture/Table/Figure (Excel spreadsheet) |
|---|
| Resource Date | 01/14/2002 |
|---|
|
| Post Date | 04/28/2006 |
|---|
| Title | FIRST SOLAR WELCOMES EU ENDORSEMENT OF ?45 MILLION AID FOR NEW SOLAR MODULE PLANT IN GERMANY |
|---|
| Link | (PDF 32 KB) Download Acrobat Reader. |
|---|
| Author | P. Vaughnn |
|---|
| Description | Phoenix, Arizona, 27 April 2006?First Solar today welcomes the European Commission?s authorization of ?45.5 million in financial incentives which the German Government plans to provide to First Solar Manufacturing GmbH for the creation of a solar module manufacturing plant in Frankfurt (Oder), region of Brandenburg. The financial incentives are now subject to approval by the German Federal government. First Solar?s final decision to proceed with the project remains subject to approval by these authorities. First Solar has started preliminary work on the project in anticipation of this approval
Upon completion, this facility will have a nominal capacity of 100MW and employ over 400 people. The total project cost is estimated at ?115M, and production is planned to begin in mid-2007. |
|---|
| Venue | 4050 E. Cotton Center #6-68, Phoenix, AZ 85040 ? t: 602-414-9300 ? e: info@firstsolar.com ? |
|---|
| Source | First Solar, Toledo, OH |
|---|
| Document Type | Press Release (Adobe Postscript file) |
|---|
| Resource Date | 04/27/2006 |
|---|
|
| Post Date | 06/29/2005 |
|---|
| Title | FIRST SOLAR ANNOUNCES A MULTI-YEAR FRAMEWORK AGREEMENT WITH GEHRLICHER GMBH |
|---|
| Link | (PDF 33 KB) Download Acrobat Reader. |
|---|
| Author | P. Vaughnn |
|---|
| Description | ?First Solar and Gehrlicher Umweltschonende Energiesysteme GmbH announce that the companies have reached a framework agreement for the supply of First Solar thin-film modules for 2005 and 2006. The modules are intended for use within the activities of the Gehrlicher Group?s Fund "We are delighted to be able to continue our successful co-operation with Gehrlicher Umweltschonende Energiesysteme GmbH in the rapidly expanding project development area," says Stephan Hansen, Managing Director of First Solar GmbH. "Gehrlicher has many years of experience in the application of thin-film modules and our continued co-operation is proof that both |
|---|
| Venue | 4050 E. Cotton Center #6-68, Phoenix, AZ 85040 ? t: 602-414-9300 ? e: info@firstsolar.com ? |
|---|
| Source | First Solar, Toledo, OH |
|---|
| Document Type | Press Release (Adobe Postscript file) |
|---|
| Resource Date | 06/27/2005 |
|---|
|
| Post Date | 06/20/2005 |
|---|
| Title | FIRST SOLAR AGREEMENT WITH BLITZSTROM |
|---|
| Link | (MS Word 25 KB) |
|---|
| Author | P. Vaughnn |
|---|
| Description | First Solar and Blitzstrom Ltd announced that the companies have entered into a framework agreement for the purchase and sale of 9 MW of First Solar thin film solar modules in 2006. First Solar began a supply relationship in 2003 with Blitzstrom and its affiliated company Beck Energy GmbH, and by the end of 2005, the companies will have cooperated to supply and install more than 14 MW of First Solar thin film modules in Germany. Story at Solarbuzz: http://www.solarbuzz.com/News/NewsNACO333.htm> and RenewableEnergyAccess: http://www.renewableenergyaccess.com/rea/market/business/viewstory?id=33463> Press at First Solar: http://www.firstsolar.com/pdf/MD-5-707%20EN%20First%20Solar%20Supply%20Agreement%20with%20Blitzstrom.pdf> Blitzstrom: http://www.blitzstrom.de/> |
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| Venue | |
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| Source | First Solar, Toledo, OH |
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| Document Type | Press Release (Word document) |
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| Resource Date | 06/2005 |
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|
| Post Date | 06/10/2005 |
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| Title | FIRST SOLAR ANNOUNCES MULTI-YEAR SUPPLY AGREEMENT WITH PHÖNIX SONNENSTROM AG |
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| Link | FSSonnJune2005 |
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| Author | P. Vaughnn |
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| Description | Advanced thin film modules to be used in 7MW of solar projects developed by Phönix SonnenStrom AG Mainz, Germany, June 1, 2005. - First Solar and Phönix SonnenStrom AG announce that the companies have entered into a framework agreement for the purchase and sale of 7MW of First Solar thin film solar modules during 2005 and 2006. Phönix SonnenStrom AG will install the First Solar modules in a number of large solar projects. |
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| Venue | 4050 E. Cotton Center #6-68, Phoenix, AZ 85040 ? t: 602-414-9300 ? e: info@firstsolar.com ? |
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| Source | First Solar, Toledo, OH |
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| Document Type | Press Release (Hypertext link) |
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| Resource Date | 06/01/2005 |
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|
| Post Date | 06/01/2005 |
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| Title | FIRST SOLAR ANNOUNCES INSURANCE POLICY TO FUND SOLAR MODULE RECLAMATION AND RECYCLING EXPENSES AT END OF PRODUCT LIFE |
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| Link | firstSolarAnnuityMay2005 |
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| Author | P. Vaughnn |
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| Description | European and U.S. Renewable Energy Leaders Endorse Innovative Insurance Program, CdTe Technology Phoenix, Arizona, May 25, 2005 ? First Solar, LLC announced today that is has completed a long term agreement with a major international insurance company to fund the estimated future costs of reclaiming and recycling First Solar modules at the end of their use. The agreement, referred to as a Reclamation and Recycling Reimbursement Policy, assures owners of First Solar modules that, at the end of solar module use, funds will be available to pay the estimated costs of transporting First Solar modules to a recycling center and recycling them into new products. |
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| Venue | 4050 E. Cotton Center #6-68, Phoenix, AZ 85040 ? t: 602-414-9300 ? e: info@firstsolar.com ? |
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| Source | First Solar, Toledo, OH |
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| Document Type | Press Release (Hypertext link) |
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| Resource Date | 05/25/2005 |
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|
| Post Date | 03/24/2005 |
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| Title | FIRST SOLAR ANNOUNCES TRIPLING OF PRODUCTION CAPACITY |
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| Link | (PDF 77 KB) Download Acrobat Reader. |
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| Author | P. Vaughnn |
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| Description | Solar announces the tripling of its production capacity to approximately 75MW in Ohio, commencing in March 2005. The expansion project will enable First Solar to produce approximately 40MW in 2006 and the full 75MW in 2007. "The expansion is prompted by strong customer demand for the product and our ability to replicate the current process while continuing to rapidly increase conversion efficiencies" said Mike Ahearn, CEO of First Solar. |
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| Venue | |
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| Source | First Solar, Toledo, OH |
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| Document Type | Press Release (Adobe Postscript file) |
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| Resource Date | 03/24/2005 |
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|
| Post Date | 02/09/2005 |
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| Title | WASTE DIRECTIVES AND THEIR IMPACT TO THE EU PV INDUSTRY |
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| Link | (PDF 27 KB) Download Acrobat Reader. |
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| Author | N/A |
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| Description | The European Directives 2002/96/EC on waste electrical and electronic equipment (WEEE) and 2002/95/EC on the restriction of the use of certain hazardous ubstances in electrical and electronic equipment (ROHS) have to be implemented by the member States in 2004 and will have a significant impact on the PV industry. |
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| Venue | EPIA |
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| Source | Deutsche Solar |
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| Document Type | Press Release (Adobe Postscript file) |
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| Resource Date | 03/20/2004 |
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|
| Post Date | 02/04/2005 |
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| Title | FIRST SOLAR'S BREAKTHROUGH TECHNOLOGY WINS R&D 100 AWARD |
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| Link | (MS Word 271 KB) |
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| Author | P. Vaughn |
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| Description | First Solar, a leader in the development and manufacture of high quality, high performance solar modules, in collaboration with the Department of Energy's National Renewable Energy Laboratory's National Center for Photovoltaics, has won a 2003 R&D 100 Award for the development of a high-rate vapor transport deposition (HRVTD) process. HRVTD is at the heart of First Solar's high volume manufacturing line which produces thin-film photovoltaic (PV) modules. Sponsored by R&D Magazine, the 41-year old awards program recognizes the 100 most significant new technologies each year, including such breakthroughs as the automated teller machine (1973), the fax machine (1975), the liquid crystal display (1980), and HDTV (1998). |
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| Venue | |
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| Sources | First Solar, Toledo, OH; National Renewable Energy Laboratory |
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| Document Type | Press Release (Word document) |
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| Resource Date | 09/10/2003 |
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|
| Post Date | 02/04/2005 |
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| Title | FIRST SOLAR SELECTED FOR TUCSON ELECTRIC POWER SOLAR PLANT EXPANSION |
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| Link | (MS Word 268 KB) |
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| Author | P. Vaughn |
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| Description | First Solar, a leader in the development and manufacture of high quality, high performance solar modules, has supplied two new solar arrays totaling 240kW for Tucson Electric Power (TEP) at the company's Springerville Generating Station. Global Solar Energy, of Tucson, Arizona, provided project management, system design and oversaw the construction of the two 120kW fixed-tilt, ground mounted arrays. This new installation increases the capacity of First Solar arrays installed at the Springerville facility to 480kWp. The first two arrays of First Solar modules were installed at TEP's Springerville facility as a beta-site in late 2001 allowing First Solar to validate product performance prior to releasing the FS Series modules for full commercial production. |
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| Venue | |
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| Sources | First Solar, Toledo, OH; Tucson Electric |
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| Document Type | Press Release (Word document) |
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| Resource Date | 08/27/2003 |
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|
Journal Articles
| Post Date | 11/17/2005 |
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| Title | PHYSICAL MODEL OF CDS BASED THIN FILM PHOTOVOLTAICS |
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| Link | Copyright protected |
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| Authors | L. Cooray, V. G. Karpov |
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| Description | We propose a simple physical model of CdS based thin film photovoltaics including the major brands of CdTe and CuIn(Ga)S component. This model is solved analytically and verified numerically. It predicts a variety of phenomena, such as the lack of carrier collection from CdS, buffer layer effects, light to dark current-voltage curve crossing and rollover, and some others. |
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| Venue | A complete copy of this paper may be requested from Victor Karpov at vkarpov@physics.utoledo.edu |
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| Source | University of Toledo |
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| Document Type | Journal Articles (Word document) |
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| Resource Date | 11/2005 |
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|
| Post Date | 11/17/2005 |
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| Title | PHYSICS OF CDTE PHOTOVOLTAICS: FROM FRONT TO BACK |
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| Link | Copyright protected |
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| Author | V. G. Karpov |
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| Description | We discuss physical mechanisms underlying the performance and stability of CdTe based thin-film PV. The processes in (i) photovoltaic junction, (ii) back contact, (iii) nonuniformities, (iv) grain boundaries, and (v) light-induced degradation are addressed including their interactions. The physics of thin film PV turns out to be quite different from that of crystalline PV. High surface-volume ratio and lack of crystallinity result in strong interfacial effects, lateral nonuniformities, and shunting-like and adhesion instabilities in thin film structures. This paper is aimed at presenting a ?big picture?; also, it suggests practical ways of improving thin-film PV. |
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| Venue | Mater. Res. Soc. Symp. Proc. Vol. 865 © 2005 Materials Research Society F10.1.1 A COPY OF THIS PAPER MAY BE ACQUIRED BY E-MAILING THE AUTHOR AT: vkarpov@physics.utoledo.edu |
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| Source | University of Toledo |
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| Document Type | Journal Articles (Word document) |
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| Resource Date | 11/2005 |
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|
| Post Date | 11/17/2005 |
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| Title | POWER GENERATION IN RANDOM DIODE ARRAYS |
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| Link | Copyright protected |
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| Author | D. Shvydka |
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| Description | We discuss nonlinear disordered systems, random diode arrays, which can represent such objects as large-area photovoltaics and ion channels of biological membranes. Our numerical modeling has revealed several interesting properties of RDAs. In particular, the geometrical distribution of nonuniformities across a RDA has only a minor effect on its integral characteristics determined by RDA parameter statistics. In the meantime, the dispersion of integral characteristics vs system size exhibits a nontrivial scaling dependence. Our theoretical interpretation here remains limited and is based on the picture of eddy currents flowing through weak diodes in the RDA. |
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| Venue | DOI: 10.1103/PhysRevB.71.115314 PACS numberssd: 89.75.2k, 84.60.Jt, 85.60.Dw, 61.43.2j A COPY OF THIS PAPER MAY BE ACQUIRED BY E-MAILING THE AUTHOR AT: vkarpov@physics.utoledo.edu |
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| Source | University of Toledo |
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| Document Type | Journal Articles (Word document) |
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| Resource Date | 10/2005 |
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|
| Post Date | 11/17/2005 |
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| Title | PIEZO-EFFECT AND PHYSICS OF CDS-BASED THIN-FILM PHOTOVOLTAICS |
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| Link | Copyright protected |
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| Author | D. Shvydka |
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| Description | We report a strong reversible piezo-effect in CdTe/CdS photovoltaics consistent with the piezo parameters of CdS. Our finding suggests a different understanding of CdS-based solar cells including CdTe- and CuIn_Ga_Se-based devices. Because the CdS film is put into compression in the device, the piezo coupling generates surface charges and the electric field opposing that of the absorber layer. The corresponding potential barrier makes CdS insulating and the device operate in a metal-insulator-semiconductor mode. Our understanding introduces the concept ofpiezo-photovoltaics and suggests specific practical implications. |
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| Venue | American Institute of Physics. _DOI: 10.1063/1.2056607 A COPY OF THIS PAPER MAY BE ACQUIRED BY E-MAILING THE AUTHOR AT: vkarpov@physics.utoledo.edu |
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| Source | University of Toledo |
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| Document Type | Journal Articles (Word document) |
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| Resource Date | 09/2005 |
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|
| Post Date | 04/05/2005 |
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| Title | CRYSTAL GROWTH AND MATERIALS RESEARCH IN PHOTOVOLTAICS: PROGRESS AND CHALLENGES |
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| Link | Copyright protected |
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| Author | T. Surek |
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| Description | Photovoltaics (PV) is solar electric power?a semiconductor-based technology that converts sunlight to electricity.Three decades of research has led to the discovery of new materials and devices and new processing techniques for lowcostmanufacturing. This has resulted in improved sunlight-to-electricity conversion ef?ciencies, improved outdoorreliability, and lower module and system costs. The manufacture and sale of PVhas grown into a $5 billion industryworldwide, with more than 740 megawatts of PVmodules shipped in 2003. This paper reviews the signi?cant progressthat has occurred in PVmaterials and devices research over the past 30 years, focusing on the advances in crystalgrowth and materials research, and examines the challenges to reaching the ultimate potential of current-generation(crystalline silicon), next-generation (thin ?lms and concentrators), and future-generation PVtechnologies. The latterincludes innovative materials and device concepts that hold the promise of signi?cantly higher conversion ef?cienciesand/or much lower costs. |
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| Venue | Journal of Crystal Growth |
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| Source | National Renewable Energy Laboratory |
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| Document Type | Journal Articles (Adobe Postscript file) |
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| Resource Date | 04/2005 |
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|
| Post Date | 02/10/2005 |
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| Title | MOLECULAR ADSORPTION-MEDIATED CONTROL OVER THE ELECTRICAL CHARACTERISTICS OF POLYCRYSTALLINE CDTE/CDS SOLAR CELLS |
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| Link | Copyright protected |
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| Authors | I. Visoly-Fisher, et al. |
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| Description | The effect of surface treatments on p-CdTe/n-CdS solar cell performance was examined. Adsorption of organic molecules with various magnitudes and directions of the dipole moment on p- CdTe resulted in controlled changes in electron affinity and surface band bending. Similar adsorption on CdTe in state-of-the-art p-CdTe/n-CdS solar cells changes the cell performance, and we explain this by a combination of increased series resistance and changes in light absorption and in cell photovoltage. While at this stage no improvement in performance has been found with these cell structures, which are the result of years of empirical optimization, the molecular effect on the photovoltage shows that it is possible in this way to control the photovoltaic effect at this junction. Separate optimization may well lead to improvement by inserting a dipole layer near the photovoltaic interface. Our results also show that this is even possible when dipole adsorption is performed on the complete polycrystalline thin-film cell. |
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| Venue | ChemPhysChem 2005 |
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| Source | Weizmann Institute |
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| Document Type | Journal Articles (Adobe Postscript file) |
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| Resource Date | 02/2005 |
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|
| Post Date | 02/09/2005 |
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| Title | E2 PHASE TRANSITION: THIN FILM AND SCHOTTKY BARRIER SUPPRESSION |
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| Link | Copyright protected |
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| Authors | V. G. Karpov, et al. |
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| Description | Electrostatic energy driven type of phase transitions in thin films. They occur under external or built-in electric fields. In the course of transition, the electrostatic energy (aE2) discharges into structural defects. This may lead to dielectric-film breakdown or Schottky-barrier suppression in semiconductor film junctions. |
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| Venue | Physical Review B 70, 155332 |
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| Source | University of Toledo |
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| Document Type | Journal Articles (Adobe Postscript file) |
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| Resource Date | 10/29/2004 |
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|
| Post Date | 02/08/2005 |
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| Title | EFFECTS OF CU AT THE DEVICE JUNCTION ON THE PROPERTIES OF CDTE/CDS PHOTOVOLTAIC CELLS |
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| Link | Copyright protected |
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| Authors | D. Albin, S. E. Asher, T. Berniard, J. W. Pankow, B. To, M. Young |
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| Description | Fabrication techniques used in processing cadmium telluride CdTe solar cell devices have been shown to introduce copper Cu into the cell structure. In fact, an accumulation of Cu in the cadmium sulfide CdS region has been seen, especially after back-contact processing. However, exactly how the presence of Cu near the device junction affects performance has yet to be determined. This study explores how CdS films are affected by Cu diffusion from a metallic layer and how these Cu-diffused layers CdS:Cu change the properties of thin-film CdS/CdTe devices. Spectrophotometric analysis shows the optical bandgap of CdS films was 2.31 eV following thermal diffusion of a 50 Å Cu layer, compared to 2.43 eV for CdS films that did not contain Cu. |
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| Venue | J. Vac. Sci. Technol B 22(5) |
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| Source | National Renewable Energy Laboratory |
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| Document Type | Journal Articles (Adobe Postscript file) |
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| Resource Date | 09/2004 |
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|
| Post Date | 02/10/2005 |
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| Title | EFFECTS OF CU IN CDS/CDTE SOLAR CELLS STUDIED WITH PATTERNED DOPING AND SPATIALLY RESOLVED LUMINESCENCE |
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| Link | Copyright protected |
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| Authors | R. T. Collins, S. D. Feldman, V. Kaydanov, T. Ohno |
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| Description | CdS/CdTe solar cells were nonuniformly doped at the backsurface of the CdTe with Cu evaporated through a shadow mask. Spatially resolved electroluminescence measurements showed strong correlation of emission intensity with the Cu pattern for all photon energies. Photoluminescence (PL) measurements performed on the exact same region showed no correlation with the Cu pattern when integrated over all energies. However, lower energy PL (located in a broad defect-related band)... |
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| Venue | Applied Physics Letters |
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| Source | Colorado School of Mines, Golden, CO |
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| Document Type | Journal Articles (Adobe Postscript file) |
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| Resource Date | 08/30/2004 |
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|
| Post Date | 02/10/2005 |
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| Title | REACH-THROUGH BAND BENDING IN SEMICONDUCTOR THIN FILMS |
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| Link | Copyright protected |
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| Authors | Y. Roussillon, et al. |
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| Description | We describe a phenomenon of reach-through band bending in thin film semiconductors. It occurs through generation of defects that change the semiconductor work function. This translates the effect of the metal presence through the semiconductor film and induces a Schottky barrier in another semiconductor tangent to the film on the opposite side reach-through band bending... |
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| Venue | Applied Physics Letters 85 (16) |
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| Source | University of Toledo |
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| Document Type | Journal Articles (Adobe Postscript file) |
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| Resource Date | 08/10/2004 |
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|
| Post Date | 02/16/2005 |
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| Title | REACTIVE-ENVIRONMENT, HOLLOW CATHODE SPUTTERING: BASIC CHARACTERISTICS AND APPLICATION TO AL2O3, DOPED ZNO, AND IN2O3 |
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| Link | Copyright protected |
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| Author | A. E. Delahoy |
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| Description | A method for thin-film deposition has been studied. The method is based on metal sputtering in a hollow cathode configuration with supply of a reactive gas in the vicinity of the substrate. The working gas and entrained sputtered atoms exit the cathode through an elongated slot. The reactive gas is thereby largely prevented from reaching the target. The basic operation of the cathode was studied using a Cu target and pulsed power excitation. These studies included the dependence of eposition rate on power, pressure, and flow rate, film thickness profiles, and film resistivity as a function of substrate conditions. Modeling was conducted to calculate the gas velocity distribution and pressure inside the cavity. |
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| Venue | J. Vac. Sci. Technol. A 22 4, Jul Aug 2004
|
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| Source | Energy Photovoltaics |
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| Document Type | Journal Articles (Adobe Postscript file) |
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| Resource Date | 08/2004 |
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|
| Post Date | 02/09/2005 |
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| Title | HOW POLYCRYSTALLINE DEVICES OUTPERFORM SINGLE CRYSTAL DEVICES... CDTE/CDS |
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| Link | Copyright protected |
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| Authors | D. Cahen, S. R. Cohen, A. Ruzin, I. Visoly-Fisher |
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| Description | |
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| Venue | Advanced Materials |
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| Source | N/A |
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| Document Type | Journal Articles (Adobe Postscript file) |
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| Resource Date | 06/04/2004 |
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|
| Post Date | 02/09/2005 |
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| Title | PHOTOLUMINESCENCE FATIGUE AND RELATED DEGRADATION IN THIN-FILM PHOTOVOLTAICS |
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| Link | Copyright protected |
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| Author | D. Shvydka |
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| Description | We observe that junction photoluminescence intensity (PL) excited by a constant power laser beam in polycrystalline CdTe/CdS solar cells gradually decreases similar to the PL fatigue in chalcogenide glasses. As a function of time it was studied at different laser beam powers and temperatures for contact-free and metallized regions. We were able to discriminate between the fatigue per se and concomitant short-time PL intensity drop due to the laser heating. The fatigue shows substantial variations between different spots on the sample. It is more profound at higher temperatures and laser beam powers where its value can be as large as 80 percent in two hours. At low temperatures and beam powers it saturates rather quickly not exceeding 10 percent of the initial PL intensity. We attribute the observed phenomenon to defect creation by the light-generated electrons and holes. The defects provide additional non-radiative recombination channels thus decreasing PL. Simultaneously, this negative feedback makes the defect-generation rate slowing down, so that the PL fatigue saturates. We propose a simple analytical model that fits the data. |
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| Venue | PACS |
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| Source | University of Toledo |
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| Document Type | Journal Articles (Adobe Postscript file) |
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| Resource Date | 2004 |
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|
| Post Date | 02/11/2005 |
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| Title | LIFE CYCLE IMPACT ANALYSIS OF CADMIUM IN CDTE PV PRODUCTION |
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| Link | Copyright protected |
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| Author | V. Fthenakis |
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| Description | Material flows and emissions in all the life stages of CdTe PV modules, from extracting refining and purifying raw materials through the production, use, and disposal or recycling of the modules. The prime focus is on cadmium flows and cadmium emissions into the environment. This assessment also compares the cadmium environmental inventories in CdTe PV modules with those of Ni-Cd batteries and of coal fuel in power plants. Previous studies are reviewed and their findings assessed in light of new data. |
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| Venue | Renewable and Sustainable Energy Reviews 8 (2004) 303?334 |
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| Source | Brookhaven National Laboratory |
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| Document Type | Journal Articles (Adobe Postscript file) |
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| Resource Date | 12/01/2003 |
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|
| Post Date | 02/10/2005 |
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| Title | CRITICAL DISORDER AND PHASE TRANSITIONS IN RANDOM DIODE ARRAYS |
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| Link | Copyright protected |
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| Author | V. G. Karpov |
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| Description | Random diode arrays represent a new class of nonlinear disordered systems related to the physics of thin-film semiconductor structures and some others. When a disorder strength grows through a certain critical value, they undergo a phase transition from almost uniform to strongly nonuniform random electric potential. A piecewise continuous topography of random potential is predicted. |
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| Venue | Physical Review Letters |
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| Source | University of Toledo |
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| Document Type | Journal Articles (Adobe Postscript file) |
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| Resource Date | 11/26/2003 |
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|
| Post Date | 02/08/2005 |
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| Title | ADMITTANCE SPECTROSCOPY REVISITED: SINGLE DEFECT ADMITTANCE AND DISPLACEMENT CURRENT |
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| Link | Copyright protected |
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| Authors | V. G. Karpov, et al. |
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| Description | A general approach to semiconductor device admittance spectroscopy analysis is developed, which describes arbitrary defect distributions, and gives the geometrical capacitance limit and the relationship between the measured conductance and capacitance. A single defect capacitance concept is introduced that facilitates the analysis. Special attention is paid to accounting for the role of displacement current, which was overlooked in the preceding work. An experimental verification of the approach is given. |
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| Venue | Journal of Applied Physics 94 (9) |
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| Source | University of Toledo |
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| Document Type | Journal Articles (Adobe Postscript file) |
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| Resource Date | 11/01/2003 |
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|
| Post Date | 02/14/2005 |
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| Title | ACCELERATED TESTING AND FAILURE OF THIN-FILM PV MODULES |
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| Link | Copyright protected |
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| Author | T. J. McMahon |
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| Description | Packaging-related PV module failure is distinguished from cell failure, and those failures specific to thin-film modules are reviewed. These are categorized according to the type of stress that produced them, e.g., temperature, voltage, moisture, current, and thermal cycling. An example is given that shows how to relate time under accelerated stress to time in use. Diagnostic tools for locating the affected area within a large-area module are pointed out along with the importance of interpretation of the visual appearance of the different damage mechanisms. |
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| Venue | Prog. Photovolt: Res. Appl. 2004; 12:235?248 |
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| Source | National Renewable Energy Laboratory |
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| Document Type | Journal Articles (Adobe Postscript file) |
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| Resource Date | 10/17/2003 |
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|
| Post Date | 02/10/2005 |
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| Title | RANDOM DIODE ARRAYS AND MESOSCALE PHYSICS OF LARGE-AREA SEMICONDUCTOR DEVICES |
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| Link | Copyright protected |
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| Authors | V. G. Karpov, et al. |
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| Description | Large-area, thin-film semiconductor devices often exhibit strong fluctuations in electronic properties on a mesoscale level that originate from relatively weak microscopic fluctuations in material structure such as grain size, chemical composition, and film thickness. Amplification comes from the fact that electronic transport through potential barriers is exponentially sensitive to the local parameter fluctuations. These effects create new phenomena and establish the physics of large-area, thin-film devices as a distinctive field of its own, quite different from that of microelectronics. We show that (i) large-area semiconductor thin-film devices are intrinsically nonuniform in the lateral directions, (ii) the nonuniformity can span length scales from millimeters to meters depending on external drivers such as light intensity and bias, and (iii) this nonuniformity significantly impacts the performance and stability... |
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| Venue | PACS |
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| Source | University of Toledo |
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| Document Type | Journal Articles (Adobe Postscript file) |
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| Resource Date | 07/02/2003 |
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|
| Post Date | 02/10/2005 |
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| Title | SOLAR CELL WITH EXTREMELY THIN ABSORBER ON HIGHLY STRUCTURED SUBSTRATE |
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| Link | Copyright protected |
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| Authors | A. Belaidi, K. Ernst, R. Konenkamp |
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| Description | We report the optical, structural and photovoltaic properties of an extremely-thin-absorber (eta) solar cell on highly porous TiO2 substrates. Nano-crystalline absorber layers with a local thickness of only 150 nm have been prepared. This small absorber thickness allows good carrier collection even for absorber material with poor transport properties. The morphology of the highly structured TiO2 substrate produces strong internal light scattering, resulting in an enhancement of the optical path length by a factor 5. With 150 nm thick CdTe absorber layers, the eta solar cells produce an open-circuit voltage of 0.67 V and a short-circuit current of 8.9 mA cm-2 for 100 mW cm-2 illumination. Alloying the CdTe with Hg improves the short-circuit current to 15 mA cm-2. |
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| Venue | Semi. Sci. Tech 18 (2003) |
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| Source | Hahn Meitner |
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| Document Type | Journal Articles (Adobe Postscript file) |
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| Resource Date | 04/14/2003 |
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|
| Post Date | 02/09/2005 |
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| Title | DIRECT EVIDENCE FOR GRAIN-BOUNDARY DEPLETION IN POLYCRYSTALLINE CDTE FROM NANOSCALE-RESOLVED MEASUREMENTS |
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| Link | Copyright protected |
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| Authors | D. Cahen, S. R. Cohen, I. Visoly-Fisher |
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| Description | We use scanning probe microscopy-based methods for direct characterization of a single grain boundary and a single grain surface in solar cell-quality CdTe, deposited by closed-space vapor transport. We find that scanning capacitance microscopy can serve to study polycrystalline ... |
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| Venue | Applied Physics Letters |
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| Source | Weizmann Institute |
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| Document Type | Journal Articles (Adobe Postscript file) |
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| Resource Date | 02/10/2003 |
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|
| Post Date | 02/09/2005 |
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| Title | LOW-LIGHT DIVERGENCE IN PHOTOVOLTAIC PARAMETER FLUCTUATIONS |
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| Link | Copyright protected |
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| Authors | A. Compaan, V. G. Karpov, D. Shvydka |
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| Description | We study statistics of the major photovoltaic parameters with low light levels. |
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| Venue | Applied Physics Letters |
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| Source | University of Toledo |
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| Document Type | Journal Articles (Adobe Postscript file) |
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| Resource Date | 02/03/2003 |
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|
| Post Date | 02/14/2005 |
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| Title | CDS AND CD(OH)2 FORMATION DURING CD TREATMENTS OF CU(IN,GA)(S,SE)2 THIN-FILM SOLAR CELL ABSORBERS |
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| Link | Copyright protected |
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| Authors | L. Weinhardt, et al. |
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| Description | The surface modifications induced by treating Cu(In,Ga)(S,Se)2 films in an aqueous ammonia hydroxide-based solution of Cd2+ ions—as used in record Cu(In,Ga)(S,Se)2 solar cells without a CdS buffer layer—have been investigated for different Cd2+ concentrations. Employing a combination of x-ray photoelectron spectroscopy, Auger electron spectroscopy, and x-ray emission spectroscopy, it is possible to distinguish two different surface modifications. For Cd2+ concentrations below 4.5 mM in the solution we observe the formation of a CdS monolayer, while higher Cd2+ concentrations lead to the additional deposition of a cadmium hydroxide film on the Cu(In,Ga)(S,Se)2 surface. |
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| Venue | APPLIED PHYSICS LETTERS VOLUME 82, NUMBER 4 27 JANUARY 2003 |
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| Source | University of Wurzburg |
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| Document Type | Journal Articles (Adobe Postscript file) |
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| Resource Date | 01/27/2003 |
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| Post Date | 02/14/2005 |
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| Title | A LABORATORY TECHNIQUE FOR THE EVALUATION OF ELECTROCHEMICAL TRANSPARENT CONDUCTIVE OXIDE DELAMINATION FROM GLASS SUBSTRATES |
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| Link | Copyright protected |
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| Authors | A. E. Delahoy, K. W. Jansen |
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| Description | A rapid laboratory technique has been developed to evaluate the susceptibility of the transparent conductive oxide (TCO)... |
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| Venue | Thin Solid Films 423 (2003) |
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| Source | Energy Photovoltaics |
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| Document Type | Journal Articles (Adobe Postscript file) |
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| Resource Date | 10/29/2002 |
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| Post Date | 02/08/2005 |
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| Title | BIAS-DEPENDENT PHOTOLUMINESCENCE IN CDTE PHOTOVOLTAICS |
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| Link | Copyright protected |
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| Authors | A. Compaan, V. G. Karpov, D. Shvydka |
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| Description | We show that external bias significantly affects the photoluminescence (PL) in CdTe photovoltaics. The main observations are: (1) reverse bias suppresses PL, (2) PL increases with moderate forward bias and tends to saturate when it is above the open-circuit voltage... |
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| Venue | Applied Physics Letters |
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| Source | University of Toledo |
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| Document Type | Journal Articles (Adobe Postscript file) |
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| Resource Date | 04/29/2002 |
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| Post Date | 02/09/2005 |
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| Title | EFFECTS OF NONUNIFORMITY IN THIN-FILM PHOTOVOLTAICS |
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| Link | Copyright protected |
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| Authors | A. Compaan, V. G. Karpov, D. Shvydka |
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| Description | We discuss the physical origin and effects of micrononuniformities on thin-film photovoltaics. The key factors are the large device area and the presence of potential barriers in the grain boundaries (for polycrystallinefilms)... |
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| Venue | Applied Physics Letters |
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| Source | University of Toledo |
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| Document Type | Journal Articles (Adobe Postscript file) |
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| Resource Date | 04/09/2002 |
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| Post Date | 02/09/2005 |
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| Title | NONLOCAL RESPONSE IN CDTE PHOTOVOLTAICS |
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| Link | Copyright protected |
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| Authors | A. Compaan, V. G. Karpov, D. Shvydka |
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| Description | We have studied the nonlocal photovoltaic response to a laser beam in CdTe/CdS solar cells. The laser-generated plasma is shown to spatially decay over a considerable distance that depends on the device lateral resistance and laser beam power. This affects open circuit voltage far from the laser spot. For the case when the lateral resistance is dominated by the transparent conductive oxide (in completed devices)... |
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| Venue | Journal of Applied Physics |
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| Source | University of Toledo |
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| Document Type | Journal Articles (Adobe Postscript file) |
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| Resource Date | 03/06/2002 |
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| Post Date | 02/10/2005 |
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| Title | SHUNT SCREENING, SIZE EFFECTS AND I/V ANALYSIS OF THIN FILMS |
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| Link | Copyright protected |
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| Author | N/A |
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| Description | We present an analytical model that quantitatively describes the physics behind shunting in thin film photovoltaics and predicts size-dependent effects in the I/V characteristics of solar cells. The model consists of an array of microdiodes and a shunt in parallel between the two electrodes, one of which mimics the transparent conductive oxide and has a finite resistance. We introduce the concept of the screening length L, over which the shunt affects the system electric potential. The nature of this screening is that the system generates currents in response to the point perturbation caused by the shunt. L is expressed explicitly in the terms of the system parameters. We find the spatial distribution of the electric potential in the system and its I/V characteristics. The measured I/V characteristics depend on the relationship between the cell size between l and L... |
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| Venue | Journal of Applied Physics 89 (9) |
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| Source | University of Toledo |
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| Document Type | Journal Articles (Adobe Postscript file) |
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| Resource Date | 02/05/2001 |
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| Post Date | 02/09/2005 |
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| Title | ELECTRON-BEAM INDUCED DEGRADATION IN CDTE PHOTOVOLTAICS |
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| Link | Copyright protected |
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| Authors | G. Dorer, D. Grecu, R. Harju, V. G. Karpov |
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| Description | We used electron beam induced current (EBIC) to measure degradation of CdTe photovoltaic cells. We have observed that: the EBIC signal shows a considerable, continuous degradation depending on the electron-beam current, scan area, energy, and sample treatment; the characteristic degradation time fluctuates between different spots on the same sample... |
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| Venue | Journal of Applied Physics |
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| Source | First Solar, Toledo, OH |
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| Document Type | Journal Articles (Adobe Postscript file) |
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| Resource Date | 08/15/2000 |
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| Post Date | 02/09/2005 |
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| Title | INFLUENCE OF SURFACE COMPOSITION ON BACK-CONTACT PERFORMANCE IN CDTE:CDS PV DEVICES |
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| Link | Copyright protected |
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| Authors | D. Albin, D. King, D. Levi |
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| Description | The atomic composition of the surface of the CdTe layer in a CdTe:CdS photovoltaic device has a significant influence on the quality of the electrical contact to this layer. This paper reports the results of a systematic study that correlates the composition of the back surface as measured with X-ray photoelectron spectroscopy XPS with pre-contact processing and device performance. We found that certain processing steps produce an oxide layer that degrades device performance... |
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| Venue | Progress in PV |
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| Source | National Renewable Energy Laboratory |
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| Document Type | Journal Articles (Adobe Postscript file) |
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| Resource Date | 05/10/2000 |
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| Post Date | 02/11/2005 |
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| Title | PHOTOVOLTAICS: ENVIRONMENTAL, HEALTH AND SAFETY ISSUES AND PERSPECTIVES |
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| Link | Copyright protected |
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| Authors | V. Fthenakis, P. D. Moskowitz |
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| Description | The photovoltaic (PV) industry must continue its pro-active approach to prevent accidents and environmental damage, and to sustain PV's inherent environmental, health, and safety (EHS) advantages. This paper presents an overview of EHS issues related to current and emerging PV technologies and gives examples of this pro-active approach. We summarize the hazards related to potential accidental releases of toxic or flammable gases used in photovoltaic cell production, and strategies for reducing such risks (e.g., choosing material and process options which inherently have small risks, and preventing accident-initiating events). Other issues discussed herein include reducing the use of toxic or carcinogenic materials in powder form, managing liquid hazardous waste, and recycling solid waste and spent modules. As the PV industry approaches these issues and mitigation strategies in a vigilant, systematic way, the risk to the industry, the workers, and the public will become minimal. An example is also discussed of environmental benefits from a large scale PV implementation, that is the potential of PV in reducing carbon dioxide emissions. |
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| Venue | Progress in Photovoltaics, Millenium Issue, 8, 27-38,2000 |
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| Source | Brookhaven National Laboratory |
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| Document Type | Journal Articles (Adobe Postscript file) |
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| Resource Date | 2000 |
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