Theoretical modeling of InAsSb/AlAsSb barrier detectors for higher-operation-temperature conditions

Abstract

InAsSb is considered as an alternative to HgCdTe ternary alloy as far as infrared (IR) detection systems are concerned. Lately, there has been an enormous progress in the development of InAsSb focal plane arrays. High-operating-temperature conditions were successfully achieved with A III B V unipolar barrier structures including InAsSb/AlAsSb and InAs/AlAsSb material systems. The performance of medium-wavelength IR InAsSb-based nB n nn + detectors is examined theoretically. Since there is no depletion layer in the active layer of such devices, the generation-recombination and trap-assisted tunneling mechanisms are suppressed, leading to lower dark currents in bariode detectors in comparison with standard diodes. Detailed analysis of the detector performance (such as dark current, dynamic resistance area product, and detectivity) versus bias voltage and operating temperatures are performed by pointing out optimal working conditions. The theoretical predictions of bariode parameters are compared with experimental data published in the literature. Finally, the bariode performance is compared with standard InAsSb photodiodes operated at room temperature.