US 7,485,476 B2
Terahertz radiating device based on semiconductor coupled quantum wells
Boris Laikhtman, Jerusalem (Israel); and Leonid Shvartsman, Jerusalem (Israel)
Assigned to Yissum Research Development Company of the Hebrew University of Jerusalem, Jerusalem (Israel)
Filed on Jul. 18, 2006, as Appl. No. 11/488,186.
Application 11/488186 is a continuation in part of application No. 10/743268, filed on Dec. 23, 2003, granted, now 7,176,498.
Claims priority of provisional application 60/492728, filed on Aug. 06, 2003.
Prior Publication US 2007/0054427 A1, Mar. 08, 2007
Int. Cl. H01L 21/00 (2006.01)
U.S. Cl. 438—22  [438/45; 438/46; 438/47; 257/E33.008] 41 Claims
OG exemplary drawing
 
1. A method of fabricating a semiconductor device operable to generate a THz spectral range radiation in response to an external field, the method comprising forming a heterostructure from selected layers, wherein
the layers include at least first and second semiconductor layers made of materials having a certain initial overlap between the valence band of the second layer material and the conduction band of the first layer material, the heterostructure layers being arranged with a selected layout providing a quantum mechanical coupling between an electron quantum well (EQW) in said first layer and a hole quantum well (HQW) in said second layer,
the layout of the layers of the heterostructure is selected so as to define a predetermined arrangement of a plurality of energy subbands and a predetermined dispersion of these subbands to define a desired effective overlap between the energy subbands of said conduction and valence bands,
thereby enabling the device operation for generation of the THz spectral range radiation originating from multiple radiative transitions of non-equilibrium carriers including at least one transition from transitions between the following: energy subbands of the EQW, energy subbands of the HQW, and ground energy electron subband of the EQW and ground energy hole subband of the HQW.