title: Enhancing Photoresponsivity of Self-Aligned MoS2 Field-Effect Transistors by Piezo-Phototronic Effect from GaN Nanowires.
abstract: We report high-performance self-aligned MoS2 field-effect transistors (FETs) with enhanced photoresponsivity by the piezo-phototronic effect. The FETs are fabricated based on monolayer MoS2 with a piezoelectric GaN nanowire (NW) as the local gate, and a self-aligned process is employed to define the source/drain electrodes. The fabrication method allows the preservation of the intrinsic property of MoS2 and suppresses the scattering center density in the MoS2/GaN interface, which results in high electrical and photoelectric performances. MoS2 FETs with channel lengths of ∼200 nm have been fabricated with a small subthreshold slope of 64 mV/dec. The photoresponsivity is 443.3 A·W(-1), with a fast response and recovery time of ∼5 ms under 550 nm light illumination. When strain is introduced into the GaN NW, the photoresponsivity is further enhanced to 734.5 A·W(-1) and maintains consistent response and recovery time, which is comparable with that of the mechanical exfoliation of MoS2 transistors. The approach presented here opens an avenue to high-performance top-gated piezo-enhanced MoS2 photodetectors.
authors.affiliation: Beijing Institute of Nanoenergy and Nanosystems, National Center for Nanoscience and Technology (NCNST), Chinese Academy of Sciences , Beijing 100083, China.
authors.forename: Xingqiang
authors.initials: X
authors.lastname: Liu
authors.affiliation: Beijing Institute of Nanoenergy and Nanosystems, National Center for Nanoscience and Technology (NCNST), Chinese Academy of Sciences , Beijing 100083, China.
authors.forename: Xiaonian
authors.initials: X
authors.lastname: Yang
authors.affiliation: Beijing Institute of Nanoenergy and Nanosystems, National Center for Nanoscience and Technology (NCNST), Chinese Academy of Sciences , Beijing 100083, China.
authors.forename: Guoyun
authors.initials: G
authors.lastname: Gao
authors.affiliation: Department of Physics and Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education, Wuhan University , Wuhan 430072, China.
authors.forename: Zhenyu
authors.initials: Z
authors.lastname: Yang
authors.affiliation: Beijing Institute of Nanoenergy and Nanosystems, National Center for Nanoscience and Technology (NCNST), Chinese Academy of Sciences , Beijing 100083, China.
authors.forename: Haitao
authors.initials: H
authors.lastname: Liu
authors.affiliation: Beijing Institute of Nanoenergy and Nanosystems, National Center for Nanoscience and Technology (NCNST), Chinese Academy of Sciences , Beijing 100083, China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Li
authors.affiliation: State Key Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences , Beijing 100083, China.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Lou
authors.affiliation: State Key Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences , Beijing 100083, China.
authors.forename: Guozhen
authors.initials: G
authors.lastname: Shen
authors.affiliation: Department of Physics and Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education, Wuhan University , Wuhan 430072, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Liao
authors.affiliation: Beijing Institute of Nanoenergy and Nanosystems, National Center for Nanoscience and Technology (NCNST), Chinese Academy of Sciences , Beijing 100083, China.
authors.forename: Caofeng
authors.initials: C
authors.lastname: Pan
authors.affiliation: Beijing Institute of Nanoenergy and Nanosystems, National Center for Nanoscience and Technology (NCNST), Chinese Academy of Sciences , Beijing 100083, China.|School of Materials Science and Engineering, Georgia Institute of Technology , Atlanta, Georgia 30332-0245, United States.
authors.forename: Zhong
authors.initials: Z
authors.lastname: Lin Wang
keywords: MoS2; field-effect transistor; photodetector; piezo-phototronic effect; self-aligned