High performance nBn detectors based on InGaAsSb bulk materials for short wavelength infrared detection

Nong Li,Zhichuan Niu,Qingxuan Jia,Yingqiang Xu,Yifeng Song,Guowei Wang,Dongwei Jiang,Ju Sun

doi:10.1063/1.5124093

Abstract

We report a low dark current, high quantum efficiency nBn photodetectors based on In0.28Ga0.72As0.25Sb0.75 bulk materials with a cut-off wavelength of 3μm at room temperature. Generation-Recombination current was suppressed using an nBn design to shift deplete region from In0.28Ga0.72As0.25Sb0.75 active region into a wide band gap AlGaSb barrier region. The Arrhenius plots of R0A-1/T show that there is no Generation-Recombination current detected in nBn device, whereas pin devices have a Generation-Recombination dominant dark current at temperatures ranging from 160K to 220K. Optical characterizations at 300K show the nBn device using InGaAsSb as an absorption material has a relative high quantum efficiency. The nBn device exhibits a peak specific detectivity of 4.8×1010 Jones under 200mV reverse bias voltage at 300K. The low dark current, high quantum efficiency and band gap tunability are expected to make InGaAsSb bulk material a competitive candidate for short wavelength infrared regime.

Highlights

We report a low dark current, high quantum efficiency nBn photodetectors based on In0.28Ga0.72As0.25Sb0.75 bulk materials with a cut-off wavelength of 3μm at room temperature
Focal plane array based on type II superlattices has been fabricated.13,14. Except these 6.1 Å based superlattice materials, InGaAsSb bulk material is a good candidate15 for Short wavelength infrared (SWIR) regime, due to its scitation.org/journal/adv great flexibility in band gap tunability and relatively high quantum efficiency compared with superlattices
Lower dark current is always preferred to realize a low cooling burden system. Other than this dark current reduction achieved by utilizing lattice matched absorption materials, we further demonstrated the G-R current suppression in SWIR InGaAsSb photo detector by nBn design

Summary

Introduction

ABSTRACT We report a low dark current, high quantum efficiency nBn photodetectors based on In0.28Ga0.72As0.25Sb0.75 bulk materials with a cut-off wavelength of 3μm at room temperature. The Arrhenius plots of R0A-1/T show that there is no Generation-Recombination current detected in nBn device, whereas pin devices have a Generation-Recombination dominant dark current at temperatures ranging from 160K to 220K. Optical characterizations at 300K show the nBn device using InGaAsSb as an absorption material has a relative high quantum efficiency.

Results

Conclusion