Extended SWIR Unipolar Barrier Detectors Lattice Matched to GaSb Substrates

The extended short wavelength infrared (e-SWIR) wavelength band is in a performance gap for infrared detectors. At both shorter and longer wavelengths high performance detector technologies exist: SWIR InGaAs detectors (1.7 m cutoff), and MWIR (3-5 m cutoff) detectors such as InAs-based and GaSb-based Unipolar Barriers, MCT, and InSb. This program proposes development of high performance e-SWIR detectors with cutoff wavelengths in the 2.5 m range, based on lattice-matched InGaAsSb absorber layers on GaSb substrates. The design incorporates a unipolar barrier device architecture that enables the device to be free of the effects of surface leakage currents and generation-recombination dark currents. The design can achieve background-limited (BLIP) performance at T=210K, which is accessible by thermo-electric coolers. The program brings together unique skill sets of two small businessesAmethyst Research who specializes in infrared detector design, development and materials growth, and Attollo Engineering who specialize in FPA fabrication and camera integration. Phase I demonstrated devices exhibiting dark current within 100 times Rule 07. In this Phase II, eSWIR detector performance will achieve dark current of 10 times Rule 07 with 85% quantum efficiency, and FPAs will be fabricated and integrated into a thermoelectrically cooled camera, to assess system performance.