129
Segmentation
of the Outer Contact on P-Type Coaxial Germanium Detectors—PHDs,
777 Emory Valley Road, Suite B, Oak Ridge, TN
37830-7071; 865-481-3725
Dr.
Ethan L. Hull, Principal Investigator, ethanhull@phdsco.com
Dr.
Ethan L. Hull, Business Official, ethanhull@phdsco.com
DOE
Grant No. DE-FG02-05ER84157
Amount:
$749,000
Segmented germanium detector arrays are needed by the DOE for
the characterization of low-level radioactive samples.
In addition, the same detector arrays could perform important fundamental
physics measurements, including the search for rare-events like neutrinoless
double-beta decay. However, because
of their complexity, these segmented coaxial detectors are expensive and
available only after relatively long lead times.
Improved fabrication techniques would greatly reduce costs and improve
the availability of these segmented detectors for the low-level counting
community. Therefore, this project
will experimentally investigate alternative techniques for making segmented
contacts on p-type coaxial germanium detectors, which would be a much cheaper
alternative to the segmented n-type coaxial detectors currently proposed.
However, the difficulties associated with the segmentation of
conventional thick lithium-diffused contacts must be addressed.
Phase I experimentally evaluated detector fabrication techniques
appropriate for segmented p-type coaxial detectors, and a fabrication recipe
was established. In Phase II, the
viability of alternative segmented detector contacts, as a competitive solution
to the contacts established during Phase I, will be established. The
best overall technique will be used to fabricate a large segmented p-type
coaxial detector as a demonstration.
Commercial
Applications and other Benefits as described by the awardee:
The
new germanium detector technology should provide better detector performance at
lower cost for the measurement of low-activity radioactive sources.
Applications of interest include national security (nuclear
nonproliferation, nuclear explosion monitoring), areas of scientific importance
(e.g., new levels of sensitivity in the Majorana search for neutrinoless doublebeta
decay), medical imaging, and x-ray detection.