Patent ID: 6818917
Filing Date: 2004-11-16
Classification: B82Y,H01L

Abstract:
A multicolor infrared photodetector with photoresponse that are switched by a bias parity and tuned by a bias, magnitude comprising:a bottom ohmic contact layer for providing ohmic contact to a metal; a bottom, superlattice formed with n-type GaAs/AlxGa1-xAs coupled to said bottom ohmic contact layer and absorbing infrared in two different wavelength regions; a current blocking layer formed with undoped AlyGa1-yAs coupled to said bottom superlattice for separating said bottom superlattice and serving as an energy filter for the photoelectrons, and reducing a dark current and a current because of a barrier height; a top superlattice formed with n-type GaAs/AlxGa1-xAs coupled to said current blocking layer and absorbing infrared in two different wavelength regions said current blocking layer separating said top and bottom superlattices; and a top ohmic contact layer coupled to said top superlattice and providing ohmic contact to said metal.