HgCdTe Detectors Under Non-Equilibrium Conditions for High Operating Temperatures

High sensitivity HgCdTe infrared detector arrays operating at 77K can be tailored for response across the infrared spectrum and are commonly utilized for infrared focal plane arrays (FPAs). However, the cooling systems required to achieve the desired sensitivity makes them heavy and therefore unsuitable for many applications. Infrared arrays operating above ~200K could be thermoelectrically-cooled and integrated in lighter and more compact interceptor systems. This superior operating temperature could be provided by a system based on HgCdTe infrared detectors operating under non-equilibrium conditions. The concept is to suppress Auger recombination and the corresponding dark current, leading to dramatic increase in detector dynamic impedances and detectivities. This technology provides sensitive infrared FPA operation with response across the infrared spectrum at high temperatures, is compatible with multi-band response and large format technology, and therefore meets all major MDA sensor requirements. In Phase I, we will demonstrate high performance single detectors with response in the MWIR and LWIR bands and high operating temperature. Our goal is to achieve detectivities >10^9 cm.Hz0.5/W at operating temperature >200K. The efforts in Phase I may be extended to two-color detection, large-format full focal plane arrays and longer wavelength operation (VLWIR out to 14 um) in later phases.