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High sensitivity HgCdTe infrared detector arrays operating at 77 K can be tailored for response across the infrared
spectrum (1 to 14 μm and beyond), and are commonly utilized for high performance infrared imaging applications.
However, the cooling system required to achieve the desired sensitivity makes them costly, heavy and limits their
applicability. Reducing cooling requirements and eventually operating at temperatures that could be reached with
thermoelectric coolers can lead to lighter and more compact systems. However, at these elevated temperatures, the
absorber layer becomes intrinsic, carrier concentrations are high and Auger processes typically dominate the dark current
and noise characteristics. Auger processes can be suppressed by placing the absorber layer between an exclusion junction
and an extraction junction at reverse bias. This reduces the minority carrier concentration in the absorber by several
orders of magnitude below thermal equilibrium. The majority carrier concentration also drops significantly below
thermal equilibrium to maintain charge neutrality, eventually reaching the extrinsic doping level. This device architecture
produces a lower dark current density and lower noise at non-cryogenic temperatures than standard p-n junction
photodiodes. Due to the precise control of the layer's thicknesses and compositions that could be achieved with
molecular beam epitaxy (MBE), this technique is the method of choice for implementing these novel non-equilibrium
devices. In this work, we analyze Auger suppression in HgCdTe alloy-based device structures and determine the
operation temperature improvements expected when Auger suppression occurs. We identified critical material (absorber
dopant concentration and minority carrier lifetime) requirements that must be satisfied for optimal performance
characteristics. Experimental dark current-voltage characteristics between 120 and 300 K are fitted using numerical
simulations. Based on this, the negative differential resistance (NDR) observed in experimental data is attributed to the
full suppression of Auger-1 processes and the partial suppression of Auger-7 processes. We will also present an analysis
and comparison of our theoretical and experimental device results in structures where Auger suppression was realized.
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