Suppression of persistent photoconductivity in high gain Ga_(2)O_(3) Schottky photodetectors  

作　　者：Haitao Zhou Lujia Cong Jiangang Ma Bingsheng Li Haiyang Xu Yichun Liu 周海涛;丛璐佳;马剑钢;李炳生;徐海洋;刘益春(Key Laboratory for UV-Emitting Materials and Technology of Ministry of Education,Northeast Normal University,Changchun 130024,China)

机构地区：[1]Key Laboratory for UV-Emitting Materials and Technology of Ministry of Education,Northeast Normal University,Changchun 130024,China

出　　处：《Chinese Physics B》2021年第12期508-514,共7页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(Grant Nos.51872043,51732003,and 51902049);the National Key R&D Program of China(Grant No.2019YFA0705202);Natural Science Foundation of Jilin Province,China(Grant No.20200201076JC);the National Basic Research Program of China(Grant No.2012CB933703);“111”Project(Grant No.B13013)。

摘　　要：The defect-related photoconductivity gain and persistent photoconductivity(PPC)observed in Ga_(2)O_(3)Schottky photodetectors lead to a contradiction between high responsivity and fast recovery speed.In this work,a metal-semiconductor-metal(MSM)Schottky photodetector,a unidirectional Schottky photodetector,and a photoconductor were constructed on Ga_(2)O_(3)films.The MSM Schottky devices have high gain(>13)and high responsivity(>2.5 A/W)at 230-250 nm,as well as slow recovery speed caused by PPC.Interestingly,applying a positive pulse voltage to the reverse-biased Ga_(2)O_(3)/Au Schottky junction can effectively suppress the PPC in the photodetector,while maintaining high gain.The mechanisms of gain and PPC do not strictly follow the interface trap trapping holes or the self-trapped holes models,which is attributed to the correlation with ionized oxygen vacancies in the Schottky junction.The positive pulse voltage modulates the width of the Schottky junction to help quickly neutralize electrons and ionized oxygen vacancies.The realization of suppression PPC functions and the establishment of physical models will facilitate the realization of high responsivity and fast response Schottky devices.

关 键 词：Ga_(2)O_(3)Schottky photodetector persistent photoconductivity high gain pulse voltage oxygen vacancy 

分 类 号：TN36[电子电信—物理电子学]