High sensitivity low dark current 10 μm GaAs quantum well infrared photodetectors

Abstract

By increasing the quantum well barrier width, we have dramatically reduced the tunneling dark current by an order of magnitude and thereby significantly increased the blackbody detectivity DBB*. For a GaAs quantum well infrared detector having a cutoff wavelength of λc=10.7 μm, we have achieved DBB* =1.0×1010 cm √Hz/W at T=68 K, a temperature which is readily achievable with a cryogenic cooler.