Photoconductive multi-layer graphene photodetectors fabricated on etched silicon-on-insulator substrates  

作　　者：Yu-Bing Wang Wei-Hong Yin Qin Han Xiao-Hong Yang Han Ye Qian-Qian Lv Dong-Dong Yin 王玉冰;尹伟红;韩勤;杨晓红;叶焓;吕倩倩;尹冬冬(State Key Laboratory on Integrated Optoelectronics, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China)

机构地区：State Key Laboratory on Integrated Optoelectronics, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China

出　　处：《Chinese Physics B》2017年第2期473-476,共4页中国物理B（英文版）

基　　金：Project supported by the National Key Research and Development Program of China(Grant No.2016YFB0402404);the High-Tech Research and Development Program of China(Grant Nos.2013AA031401,2015AA016902,and 2015AA016904);the National Natural Science Foundation of China(Grant Nos.61674136,61176053,61274069,and 61435002)

摘　　要：Recently, graphene-based photodetectors have been rapidly developed. However, their photoresponsivities are generally low due to the weak optical absorption strength of graphene. In this paper, we fabricate photoconductive multi-layer graphene（MLG） photodetectors on etched silicon-on-insulator substrates. A photoresponsivity exceeding 200 A·W-1is obtained, which enables most optoelectronic application. In addition, according to the analyses of the high photoresponsivity and long photoresponse time, we conclude that the working mechanism of the device is photoconductive effect. The process of photons conversion into conducting electrons is also described in detail. Finally, according to the distinct difference between the photoresponses at 1550 nm and 808 nm, we estimate that the position of the trapping energy is somewhere between 0.4 e V and 0.76 e V, higher than the Fermi energy of MLG. Our work paves a new way for fabricating the graphene photoconductive photodetectors.Recently, graphene-based photodetectors have been rapidly developed. However, their photoresponsivities are generally low due to the weak optical absorption strength of graphene. In this paper, we fabricate photoconductive multi-layer graphene（MLG） photodetectors on etched silicon-on-insulator substrates. A photoresponsivity exceeding 200 A·W-1is obtained, which enables most optoelectronic application. In addition, according to the analyses of the high photoresponsivity and long photoresponse time, we conclude that the working mechanism of the device is photoconductive effect. The process of photons conversion into conducting electrons is also described in detail. Finally, according to the distinct difference between the photoresponses at 1550 nm and 808 nm, we estimate that the position of the trapping energy is somewhere between 0.4 e V and 0.76 e V, higher than the Fermi energy of MLG. Our work paves a new way for fabricating the graphene photoconductive photodetectors.

关 键 词：graphene photodetector photoconductive effect 

分 类 号：TN15[电子电信—物理电子学]