Dark current behaviour of type-II superlattice longwave infrared photodetectors under proton irradiation

Abstract

In this work, the authors investigated the influence of proton-irradiation on the dark current of XBp longwave infrared InAs/GaSb type-II superlattice barrier detectors, showing a cut-off wavelength from 11 µm to 13 µm at 80 K. The proton irradiations were performed with 63 MeV protons and fluences up to 8∙1011 H+/cm² on a type-II superlattice detector kept at cryogenic (100 K) or room temperature (300 K). The irradiation temperature of the detector is a key parameter influencing the effects of proton irradiation. The dark current density increases due to displacement damage dose effects and this increase is more important when the detector is proton-irradiated at room temperature rather than at cryogenic temperature.