High-operating-temperature (HOT) infrared detectors based on antimonide heterostructures

In this study, InAs/InAsSb based p-i-n and nBn detector structures were designed for mid-infrared region detection. The designed detector structures were grown on GaSb substrates by molecular beam epitaxy technique. By changing parameters such as growth rate, flux modulation and substrate vendor, crystal quality of the grown structures were monitored. The dark current and spectral responses of the detectors were evaluated by fabricating single pixel devices. In addition, recombination mechanisms and localized states in the absorber and barrier layers were investigated using the photoluminescence technique and the results of the experimental studies were presented. With the radiometric approach, parameters affecting system performance such as well fill, dynamic range and bit losses were investigated for an InAs/InAsSb based imager at different scene temperatures. Detector parameters such as quantum efficiency, noise equivalent temperature differences and pixel non-uniformity were considered in the analysis.