High-performance extended short-wavelength infrared PBn photodetectors based on InAs/GaSb/AlSb superlattices

Abstract

High performance short-wavelength infrared PBn photodetectors based on InAs/GaSb/AlSb superlattices on GaSb substrate have been demonstrated. At 300K, the device exhibits a 50% cut-off wavelength of ~2.1 μm as predicted from the band structure calculation; the device responsivity peaks at 0.85 A/W, corresponding to a QE of 56% for 2.0 μm-thick absorption region. The dark current density of 1.03 × 10−3 A/cm2 is obtained under -50mV applied bias. The device exhibits a saturated dark current shot noise limited specific detectivity (D*) of 3.29×1010cm·Hz1/2/W (at a peak responsivity of 2.0μm) under -50mV of applied bias.