Heterostructured graphene quantum dot/WSe2/Si photo-detector with suppressed dark current and improved detectivity  

作　　者：Mengxing Sun Qiyi Fang Dan Xie Yilin Sun Liu Qian Jianlong Xu Peng Xiao Changjiu Teng Weiwei Li Tianling Ren Yanfeng Zhang 

机构地区：[1]Institute ofMicroelectronics & Tsinghua National Laboratory for Information Science and Technology (TNList), Tsinghua University, Beijing 100084, China [2]Department of Materials Science and Engineering, College of Engineering, Peking University, Beijing 100084, China [3]Department of Chemistry, Tsinghua University, Belling 100084, China [4]Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou 215123, China

出　　处：《Nano Research》2018年第6期3233-3243,共11页纳米研究（英文版）

摘　　要：A high-performance heterojunction photodetector is formed by combining an n-type Si substrate with p-type monolayer WSe2 obtained using physical vapor deposition. The high quality of the WSe2/Si heterojunction is demonstrated by the suppressed dark current of I nA and the extremely high rectification ratio of 107. Under illumination, the heterojunction exhibits a wide photoresponse range from ultraviolet to near-infrared radiation. The introduction of graphene quantum dots （GQDs） greatly elevates the photodetective capabilities of the heterojunction with strong light absorption and long carrier lifetimes. The GQDs/WSe2/Si heterojunction exhibits a high responsivity of -707 mA·W^-1, short response time of 0.2 ms, and good specific detectivity of -4.51×10^9 Jones. These properties suggest that the GQDs/WSe2/Si heterojunction holds great potential for application in future high- performance photodetectors.A high-performance heterojunction photodetector is formed by combining an n-type Si substrate with p-type monolayer WSe2 obtained using physical vapor deposition. The high quality of the WSe2/Si heterojunction is demonstrated by the suppressed dark current of I nA and the extremely high rectification ratio of 107. Under illumination, the heterojunction exhibits a wide photoresponse range from ultraviolet to near-infrared radiation. The introduction of graphene quantum dots （GQDs） greatly elevates the photodetective capabilities of the heterojunction with strong light absorption and long carrier lifetimes. The GQDs/WSe2/Si heterojunction exhibits a high responsivity of -707 mA·W^-1, short response time of 0.2 ms, and good specific detectivity of -4.51×10^9 Jones. These properties suggest that the GQDs/WSe2/Si heterojunction holds great potential for application in future high- performance photodetectors.

关 键 词：HETEROJUNCTION PHOTODETECTOR SI WSe2 graphene quantum dots 

分 类 号：TN215[电子电信—物理电子学] U270.7[机械工程—车辆工程]