We propose a high quantum efficiency (QE) 1024x1024 longwave infrared focal plane array (LWIR FPA) and CAMERA with ~ 12 micron cutoff wavelength made from bandgap-engineered Type-II InAs/GaSb strained layer superlattice (SLS) photodiodes. FPA/camera performance goals include QE > 50% and temporal noise equivalent difference in temperature (NEDT) < 30 mK while operating at a temperature > 60K with a fast integration time < 0.5 ms and F/4 optics. In Phase I, we developed and delivered a high-performance 640x512 SLS FPA as proof of concept, clearly demonstrating the viability of bandgap-engineered Group III-V InAs/GaSb/AlSb materials as a real cost-effective alternative to mercury cadmium telluride (MCT) for NASA's requirements for high-QE LWIR FPAs. Phase II will build on Phase I by expanding array format, shrinking pixel pitch, improving QE, and packaging and delivering the FPA in a camera that NASA can field-test to evaluate this novel sensor technology. The 12 micron cutoff, high QE, and relatively high operating temperature of SLS are expected to be of particular benefit to NASA's LANDSAT and HyspIRI projects.
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