Study of Generation Recombination Process in Type II InAs/GaSb Superlattices for High Performance VLWIR Detectors

Very long wave infrared (VLWIR or lambda > 15 micron) photon detectors are highly needed in a number of missile defense missions. Type II InAs/GaSb superlattices represent the most promising material system capable of delivering a more affordable and producible focal plane array (FPA) technology than the current technology, while at the same time exhibiting similar or better performance than current technology in this spectral band. However, one of the major obstacle in the development of such FPAs remains the generation-recombination (G-R) current which still dominates the dark current in these photodetectors. It is here proposed to study the feasibility of reducing the G-R current in such type II superlattice photodetectors through advanced modeling and design of the superlattice structures in close correlation with detector growth, fabrication and performance measurement results.