Superlattice Materials for the Next Generation of Long Wavelength Infrared Detectors

New infrared (IR) detector materials with high sensitivity, multi-spectral capability, improved uniformity and lower manufacturing costs are required for numerous space-based infrared imaging applications. To meet these stringent requirements, new materials must be designed and grown using semiconductor heterostructures, such as quantum wells and superlattices, to tailor new optical and electrical properties unavailable in the current generation of materials. One of the most promising materials is a strained layer supperlattice (SLS) composed of thin InAs and GaInSb layers. While this material shows theoretical and early experimental promise, there are still several materials growth and processing issues to be addressed before this material can be transitioned to the next generation of infrared detector arrays. Our research is focused on addressing the basic materials design, growth, optical properties, and electronic transport issue of these superlattices.