High-performance self-powered ultraviolet photodetector in SnO_(2)microwire/p-GaN heterojunction using graphene as charge collection medium  

作　　者：Tong Xu Mingming Jiang Peng Wan Yang Liu Caixia Kan Daning Shi 

机构地区：[1]College of physics,MIIT Key Laboratory of Aerospace Information Materials and Physics,Key Laboratory for Intelligent Nano Materials and Devices,Nanjing University of Aeronautics and Astronautics,Nanjing 211106,China

出　　处：《Journal of Materials Science & Technology》2023年第7期183-192,共10页材料科学技术（英文版）

基　　金：This work was financially supported by the National Natural Science Foundation of China(NSFC)(Nos.11974182 and 11874220);Fundamental Research Funds for the Central Universities(No.NC2022008);Funding for Outstanding Doctoral Dissertation in NUAA(No.BCXJ22-14).

摘　　要：Graphene monolayer has been extensively applied as a transparency electrode material in photoelectronic devices due to its high transmittance,high carrier mobility,and ultrafast carrier dynamics.In this study,a high-performance self-powered photodetector,which is made of a SnO_(2)microwire,p-type GaN film,and monolayer graphene transparent electrode,was proposed and fabricated.The detector is sensitive to ultraviolet light signals and illustrates pronounced detection performances,including a peak respon-sivity∼223.7 mA W^(-1),a detectivity∼6.9×10^(12)Jones,fast response speed(rising/decaying times∼18/580μs),and excellent external quantum efficiency∼77%at 360 nm light illumination without exter-nal power supply.Compared with the pristine SnO_(2)/GaN photodetector using ITO electrode,the device performances of responsivity and detectivity are significantly increased over 6×10^(3)%and 3×10^(3)%,respectively.The performance-enhanced characteristics are mainly attributed to the high-quality het-erointerface of n-SnO_(2)/p-GaN,the highly conductive capacity,and the unique transparency of graphene electrodes.Particularly,the built-in potential formed at the SnO_(2)/GaN heterojunction interface could be strengthened by the Schottky potential barrier derived from the graphene electrode and SnO_(2)wire,en-hancing the carrier collection efficiency through graphene as a charge collection medium.This work is of great importance and significance to developing excellent-performance ultraviolet photodetectors for photovoltaic and optoelectronic applications in a self-powered operation manner.

关 键 词：Self-powered photodetector SnO_(2)microwires Monolayer graphene electrode HETEROJUNCTION Schottky barrier 

分 类 号：TN23[电子电信—物理电子学]