Novel Sb-based materials for uncooled infrared photodetector applications

We have developed low-pressure metalorganic chemical vapor deposition techn ology for the growth of novel III-V Sb-based compounds such as InTlSb, InTl AsSb. and InSbSi. The incorporation of Tl and Si is investigated with vario us characterization techniques. Preliminary infrared photodetectors based o n these materials are fabricated and tested. The maximum responsivity of an In0.96Tl0.04Sb photodetector is about 6.64 V/W at 77 K, corresponding to a Johnson-noise-limited detectivity of about 7.64 x 10(8) cm Hz(1/2)/W. Phot oresponse of the In0.94Tl0.06Sb photodetector has been extended to 11 mum a t 300K. Infrared photoresponse up to 15 mum is achieved from the InTlAsSb a lloy at room temperature. We also demonstrate the uncooled InSbBi photodete ctor operating in the 8-12 mum range. The voltage responsivity at 10.6 mum is about 1.9mV/W at 300K and the corresponding Johnson-noise-limited detect ivity is 1.2 x 10(6) cm Hz(1/2)/W. The carrier lifetime is estimated to be 0.7ns. (C) 2000 Elsevier Science B.V. All rights reserved.