High Sb Content T2SLS Detectors for LWIR FLIR Imagers

OSEMI and UCSB, with support from Lockheed-Martin’s Santa Barbara Focalplane, propose to advance Type-2 Strained-Layer Superlattice (T2SLS) long wave infrared (LWIR) materials and detector technology. We specifically propose to investigate adding increased amounts of lead (Sb) in indium arsenide tin (InAsSb) - based SLS structures to increase LWIR absorption and detector quantum efficiency. We shall also investigate growth conditions to minimize defects so that our cryogenic dark current may approach ‘Rule 07’ performance that defines the very best mercury cadmium telluride (MCT) Detector material. Our end goal in the Phase I, Phase II program is to expand the basic science and growth control of T2SLS growth on GaSb substrates such that by the end Phase II T2SLS LWIR FPAs can reproducibly produced with performance that rival even the very best MCT grown on II-VI substrates while providing highly improved image uniformity, reduced image defect artifacts with dramatically lower cost. Approved for Public Release | 21-MDA-11013 (19 Nov 21)