Thickness-modulated in-plane Bi2O2Se homojunctions for ultrafast high-performance photodetectors  

作　　者：Cheng-Yun Hong Gang-Feng Huang Wen-Wen Yao Jia-Jun Deng Xiao-Long Liu 洪成允;黄刚锋;要文文;邓加军;刘小龙(Renewable Energy School,North China Electric Power University,Beijing 102206,China;Department of Mathematics and Physics,North China Electric Power University,Beijing 102206,China;State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources and Beijing Key Laboratory of Energy Safety and Clean Utilization,North China Electric Power University,Beijing 102206,China)

机构地区：[1]Renewable Energy School,North China Electric Power University,Beijing 102206,China [2]Department of Mathematics and Physics,North China Electric Power University,Beijing 102206,China [3]State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources and Beijing Key Laboratory of Energy Safety and Clean Utilization,North China Electric Power University,Beijing 102206,China

出　　处：《Chinese Physics B》2019年第12期363-369,共7页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(Grant No.61705066);the Open Fund of State Key Laboratory of Information Photonics and Optical Communications(Beijing University of Posts and Telecommunications),China(Grant No.IPOC2018B004);the National Key Research and Development Program,China(Grant No.2016YFA0202401)

摘　　要：Bi2O2Se thin film could be one of the promising material candidates for the next-generation electronic and optoelectronic applications. However, the performance of Bi2O2Se thin film-based device is not fully explored in the photodetecting area. Considering the fact that the electrical properties such as carrier mobility, work function, and energy band structure of Bi2O2Se are thickness-dependent, the in-plane Bi2O2Se homojunctions consisting of layers with different thicknesses are successfully synthesized by the chemical vapor deposition(CVD) method across the terraces on the mica substrates,where terraces are created in the mica surface layer peeling off process. In this way, effective internal electrical fields are built up along the Bi2O2Se homojunctions, exhibiting diode-like rectification behavior with an on/off ratio of 102, what is more, thus obtained photodetectors possess highly sensitive and ultrafast features, with a maximum photoresponsivity of 2.5 A/W and a lifetime of 4.8 μs. Comparing with the Bi2O2Se uniform thin films, the photo-electric conversion efficiency is greatly improved for the in-plane homojunctions.Bi2O2Se thin film could be one of the promising material candidates for the next-generation electronic and optoelectronic applications. However, the performance of Bi2O2Se thin film-based device is not fully explored in the photodetecting area. Considering the fact that the electrical properties such as carrier mobility, work function, and energy band structure of Bi2O2Se are thickness-dependent, the in-plane Bi2O2Se homojunctions consisting of layers with different thicknesses are successfully synthesized by the chemical vapor deposition（CVD） method across the terraces on the mica substrates,where terraces are created in the mica surface layer peeling off process. In this way, effective internal electrical fields are built up along the Bi2O2Se homojunctions, exhibiting diode-like rectification behavior with an on/off ratio of 102, what is more, thus obtained photodetectors possess highly sensitive and ultrafast features, with a maximum photoresponsivity of 2.5 A/W and a lifetime of 4.8 μs. Comparing with the Bi2O2Se uniform thin films, the photo-electric conversion efficiency is greatly improved for the in-plane homojunctions.

关 键 词：Bi2O2Se in-plane homojunction thickness modulation PHOTODETECTORS 

分 类 号：O48[理学—固体物理]