InAsSb and InPSb materials for mid infrared photodetectors

III-V semiconductor materials are under active investigation for use as optical detectors in the mid infrared wavelength region from 3 to 12 µm. In this paper we summarize recent progress on the development of III-V materials for this application based on the material InAsSb. We first present the results of investigations in the use of strained balanced type II superlattices of InAsSb/InAs to extend the absorption wavelength of this material system beyond the limits of the maximum InAsSb bulk value. We present results on the growth of InPSb heterojunction structures with the aim of reducing thermal diffusion current and surface leakage. Finally we present some preliminary device results indicating the promise of this material system.