title: Tuning of the electronic characteristics of ZnO nanowire field effect transistors by proton irradiation.
abstract: We demonstrated a controllable tuning of the electronic characteristics of ZnO nanowire field effect transistors (FETs) using a high-energy proton beam. After a short proton irradiation time, the threshold voltage shifted to the negative gate bias direction with an increase in the electrical conductance, whereas the threshold voltage shifted to the positive gate bias direction with a decrease in the electrical conductance after a long proton irradiation time. The electrical characteristics of two different types of ZnO nanowires FET device structures in which the ZnO nanowires are placed on the substrate or suspended above the substrate and photoluminescence (PL) studies of the ZnO nanowires provide substantial evidence that the experimental observations result from the irradiation-induced charges in the bulk SiO(2) and at the SiO(2)/ZnO nanowire interface, which can be explained by a surface-band-bending model in terms of gate electric field modulation. Our study on the proton-irradiation-mediated functionalization can be potentially interesting not only for understanding the proton irradiation effects on nanoscale devices, but also for creating the property-tailored nanoscale devices.
authors.affiliation: Department of Materials Science and Engineering, Gwangju Institute of Science and Technology, Gwangju 500-712, Korea.
authors.forename: Woong-Ki
authors.initials: WK
authors.lastname: Hong
authors.forename: Gunho
authors.initials: G
authors.lastname: Jo
authors.forename: Jung Inn
authors.initials: JI
authors.lastname: Sohn
authors.forename: Woojin
authors.initials: W
authors.lastname: Park
authors.forename: Minhyeok
authors.initials: M
authors.lastname: Choe
authors.forename: Gunuk
authors.initials: G
authors.lastname: Wang
authors.forename: Yung Ho
authors.initials: YH
authors.lastname: Kahng
authors.forename: Mark E
authors.initials: ME
authors.lastname: Welland
authors.forename: Takhee
authors.initials: T
authors.lastname: Lee