Translator Disclaimer
31 May 2005 Type-II InAs/GaInSb superlattices for infrared detection: an overview
Author Affiliations +
Superlattices composed of InAs and GaSb layers were first proposed for infrared detection in 1978. Later work by Smith and Mailhoit extended this premise to model InAs and InGaSb ternary layers for infrared detection in the long wavelength infrared range. What makes this material system so interesting is that these superlattice materials are essentially the III-V equivalent of HgCdTe materials. They have comparable absorption coefficients, the cut-off wavelengths can be continuously adjusted from short wavelength infrared to very long wavelength infrared (VLWIR), and photovoltaic operation is possible. One difference between these two materials is that with the superlattices the energy band structure, as well as the band gap, can be tailored to enhance detector performance. The band structure tailoring provides the superlattices with some advantages over HgCdTe alloys, particularly for very narrow band gaps. These superlattice advantages are a higher electron effective mass and large separation of the heavy and light-hole bands to suppress Auger recombination. These inherent properties of the InAs/GaInSb superlattices have made them an attractive material for VLWIR applications. As the type-II superlattice materials and devices mature, they will play a significant role as an alternative material for photovoltaic focal plane arrays in the LWIR and MWIR regimes as well. This paper provides an overview of the type-II superlattice development, accomplishments and issues.
© (2005) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Gail J. Brown "Type-II InAs/GaInSb superlattices for infrared detection: an overview", Proc. SPIE 5783, Infrared Technology and Applications XXXI, (31 May 2005);

Back to Top