InAsSb strained-layer superlattices for long wavelength detector applications

Abstract

InAsSb strained-layer superlattices (SLS’s) are proposed as novel III–V semiconductor materials with the potential for long wavelength intrinsic detector applications. Theoretical studies of the band gaps of various InAs0.4Sb0.6/InAs1−xSbx SLS’s with x > 0.6 have been carried out. The results indicate that the wavelength response of various SLS’s with x ≳ 0.73 can be extended to 12 μm at 77 K through the intentional use of layer strains. These new structures offer the metallurgical and processing advantages of III–V semiconductors for 12 μm detector applications. Further advantages include a weaker dependence of the SLS band gap on composition and reduced band-to-band tunneling in the SLS compared to bulk Hg0.8Cd0.2Te.