High-performance short-wavelength infrared photodetectors based on type-II InAs/InAs1-xSbx/AlAs1-xSbx superlattices

Abstract

We present a high-performance short-wavelength infrared n-i-p photodiode, whose structure is based on type-II superlattices with InAs/InAs1-xSbx/AlAs1-xSbx on GaSb substrate. At room temperature (300K) with front-side illumination, the device shows the peak responsivity of 0.47 A/W at 1.6mm, corresponding to 37% quantum efficiency at zero bias. At 300K, the device has a 50% cut-off wavelength of ~1.8mm. For −50mV applied bias at 300 K the photodetector has dark current density of 9.6x10-5 A/cm2 and RxA of 285 Ω•cm2, and it revealed a detectivity of 6.45x1010 cm•Hz1/2/W. Dark current density reached to 1.3x10-8 A/cm2 at 200 K, with 36% quantum efficiency which leads to the detectivity value of 5.66x1012 cm•Hz1/2/W.