title: Improving the field-effect performance of Bi2S3 single nanowires by an asymmetric device fabrication.
abstract: High-quality Bi2 S3 nanowires are synthesized by chemical vapor deposition and their intrinsic photoresponsive and field-effect characteristics are explored in detail. Among the studied Au-Au, Ag-Ag, and Au-Ag electrode pairs, the device with stepwise band alignment of asymmetric Au-Ag electrodes has the highest mobility. Furthermore, it is shown that light can cause a sevenfold decrease of the on/off ratio. This can be explained by the photoexcited charge carriers that are more beneficial to the increase of Ioff than Ion . The photoresponsive properties of the asymmetric Au-Ag electrode devices were also explored, and the results show a photoconductive gain of seven with a rise time of 2.9 s and a decay time of 1.6 s.
authors.affiliation: State Key Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, P.O. Box 912, Beijing100083 (China).
authors.forename: Fangyuan
authors.initials: F
authors.lastname: Lu
authors.forename: Renxiong
authors.initials: R
authors.lastname: Li
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.forename: Nengjie
authors.initials: N
authors.lastname: Huo
authors.forename: Juehan
authors.initials: J
authors.lastname: Yang
authors.forename: Yongtao
authors.initials: Y
authors.lastname: Li
authors.forename: Bo
authors.initials: B
authors.lastname: Li
authors.forename: Shengxue
authors.initials: S
authors.lastname: Yang
authors.forename: Zhongming
authors.initials: Z
authors.lastname: Wei
authors.forename: Jingbo
authors.initials: J
authors.lastname: Li
keywords: Bi2S3 nanowires; asymmetric electrodes; band alignment; carrier mobility; photoresponse