Work

pBn type short-wavelength infrared photodetector with an ultralow dark current and extended wavelength based on a strained InGaAs/GaAsSb superlattice

Year: 2024

Type: article

Abstract: An InGaAs/GaAsSb type II superlattice (T2SL) absorber is a promising alternative material for a short-wavelength infrared (SWIR) photodetector due to the largely tunable bandgap by adjusting the thickness and material composition of InGaAs and GaAsSb in each T2SL period. We demonstrate a pBn type SWIR photodetector consisting of a strained InGaAs/GaAsSb T2SL absorber and AlGaAsSb barrier. The device presents an ultralow dark current density of 1.81 × 10−4 A/cm2 and a peak responsivity of 0.38 A/W under a reverse bias of −1 V at 300 K. The detector shows a peak detectivity of 1.62 × 1011 cm·Hz1/2/W and 4.63 × 1010 cm·Hz1/2/W under a reverse bias of −1 V at 260 K and 300 K, respectively. Moreover, our photodetector demonstrates an extended 100% cutoff wavelength response up to 2.2 μm.

Source: Optics Letters

DOI: 10.1364/ol.543761