title: Controllable p-n switching behaviors of GaAs nanowires via an interface effect.
abstract: Due to the extraordinary large surface-to-volume ratio, surface effects on semiconductor nanowires have been extensively investigated in recent years for various technological applications. Here, we present a facile interface trapping approach to alter electronic transport properties of GaAs nanowires as a function of diameter utilizing the acceptor-like defect states located between the intrinsic nanowire and its amorphous native oxide shell. Using a nanowire field-effect transistor (FET) device structure, p- to n-channel switching behaviors have been achieved with increasing NW diameters. Interestingly, this oxide interface is shown to induce a space-charge layer penetrating deep into the thin nanowire to deplete all electrons, leading to inversion and thus p-type conduction as compared to the thick and intrinsically n-type GaAs NWs. More generally, all of these might also be applicable to other nanowire material systems with similar interface trapping effects; therefore, careful device design considerations are required for achieving the optimal nanowire device performances.
authors.affiliation: Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong SAR, China.
authors.forename: Ning
authors.initials: N
authors.lastname: Han
authors.forename: Fengyun
authors.initials: F
authors.lastname: Wang
authors.forename: Jared J
authors.initials: JJ
authors.lastname: Hou
authors.forename: Fei
authors.initials: F
authors.lastname: Xiu
authors.forename: SenPo
authors.initials: S
authors.lastname: Yip
authors.forename: Alvin T
authors.initials: AT
authors.lastname: Hui
authors.forename: TakFu
authors.initials: T
authors.lastname: Hung
authors.forename: Johnny C
authors.initials: JC
authors.lastname: Ho