We present results from indium antimonide and mercury cadmium telluride IR detector arrays operating at temperatures above 80K, whilst retaining high performance. Multi-layer epitaxial growth is employed to minimize thermally generated leakage currents, through the use of structures designed to control transport of charge generated outside of the active region to the diode junction and to minimize Auger generation within the active region. This enables an increase in operating temperature of a few tens of degrees in the case of background limited III-V devices, and thermoelectric operation of MCT detectors sensitive to the MWIR band. We also discuss the effects of reverse bias on diodes to actively suppress the Auger generation, and the consequent introduction of 1/f noise. Optical concentrators can be used to minimize the volume of detector material in order to gain further increases in temperature. The concentrators, based on Winston cone designs, are fabricated at each pixel by reactive ion etching directly into the detector material and its substrate, and allow a theoretical reduction in volume of a factor of up to 16. This translates into a potential additional increase in temperature of several tens of degrees.
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