Thickness-dependent enhanced optoelectronic performance of surface charge transfer-doped ReS2 photodetectors  

作　　者：Peiyu Zeng Wenhui Wang Jie Jiang Zheng Liu Dongshuang Han Shuojie Hu Jiaoyan He Peng Zheng Hui Zheng Liang Zheng Xiaojing Yao Weitao Su Dexuan Huo Zhangting Wu Zhenhua Ni Yang Zhang 

机构地区：[1]Lab for Nanoelectronics and NanoDevices,Department of Electronics Science and Technology,Hangzhou Dianzi University,Hangzhou 310018,China [2]School of Physics,Southeast University,Nanjing 211189,China [3]Jiangsu Province Special Equipment Safety Supervision and Inspection Institute,Wuxi 214170,China [4]School of Sciences,Hangzhou Dianzi University,Hangzhou 310018,China [5]College of Physics and Hebei Advanced Thin Film Laboratory,Hebei Normal University,Shijiazhuang 050024,China [6]Institute of Materials Physics,Hangzhou Dianzi University,Hangzhou 310018,China

出　　处：《Nano Research》2022年第4期3638-3646,共9页纳米研究（英文版）

基　　金：This work was supported by the National Natural Science Foundation of China(No.61904043);the Natural Science Foundation of Zhejiang Province(No.LQ19A040009).

摘　　要：Surface charge transfer doping has been widely utilized to tune the electronic and optical properties of semiconductor photodetectors based on low-dimensional materials.Although many studies have been conducted on the performance(response time,responsivity,etc.)of doped photodetectors and their mechanisms,they merely examined a specific thickness and did not systematically explore the dependence of doping effects on the number of layers.This work performs a series of investigations on ReS_(2)photodetectors with different numbers of layers and demonstrates that the p-dopant tetrafluorotetracyanoquinodimethane(F_(4)-TCNQ)converts the deep trap states into recombination centers for few-layer ReS_(2)and induces a vertical p-n junction for thicker ReS_(2).A response time of 200 ms is observed in the decorated 2-layer ReS_(2)photodetector,more than two orders of magnitude faster than the response of the pristine photodetector,due to the disappearance of deep trap states.A current rectification ratio of 30 in the F_(4)-TCNQ-decorated sandwiched ReS_(2)device demonstrates the formation of a vertical p-n junction in a thicker ReS_(2)device.The responsivity is as high as 2,000 A/W owing to the strong carrier separation of the p-n junction.Different thicknesses of ReS_(2)enable switching of the prominent operating mechanism between transforming deep trap states into recombination centers and forming a vertical p-n junction.The thicknessdependent doping effect of a two-dimensional material serves as a new mechanism and provides a scheme toward improving the performance of other semiconductor devices,especially optical and electronic devices based on low-dimensional materials.

关 键 词：Surface charge transfer doping ReS_(2) thickness response time RESPONSIVITY tetrafluorotetracyanoquinodimethane(F_(4)-TCNQ) 

分 类 号：TN382[电子电信—物理电子学]