A 2DEG back-gated graphene/AlGaN deep-ultraviolet photodetector with ultrahigh responsivity  

作　　者：Jinhui Gao Yehao Li Yuxuan Hu Zhitong Wang Anqi Hu Xia Guo 高金辉;李叶豪;胡宇轩;王志通;胡安琪;郭霞(School of Electronic Engineering,State Key Laboratory of Information Photonics and Optical Communications,Beijing University of Posts and Telecommunications,Beijing 100876,China)

机构地区：[1]School of Electronic Engineering,State Key Laboratory of Information Photonics and Optical Communications,Beijing University of Posts and Telecommunications,Beijing 100876,China

出　　处：《Chinese Physics B》2020年第12期542-546,共5页中国物理B（英文版）

基　　金：Project supported by the Research Innovation Fund for College Students of Beijing University of Posts and Telecommunications(Grant No.202002046);the National Natural Science Foundation of China(Grant No.61804012).

摘　　要：A graphene/AlGaN deep-ultraviolet(UV)photodetector is presented with ultrahigh responsivity of 3.4×105 A/W at 261 nm incident wavelength and 149 pW light power.A gain mechanism based on electron trapping at the potential well is proposed to be responsible for the high responsivity.To optimize the trade-off between responsivity and response speed,a back-gate electrode is designed at the AlGaN/GaN two-dimensional electron gas(2DEG)area which eliminates the persistent photocurrent effect and shortens the recovery time from several hours to milliseconds.The 2DEG gate is proposed as an alternative way to apply the back gate electrode on AlGaN based devices on insulating substrates.This work sheds light on a possible way for weak deep-UV light detection.

关 键 词：graphene/AlGaN deep-ultraviolet high responsivity PHOTODETECTOR 

分 类 号：TN36[电子电信—物理电子学]