title: Facile synthesis and growth mechanism of Ni-catalyzed GaAs nanowires on non-crystalline substrates.
abstract: GaAs nanowires (NWs) have been extensively explored for next generation electronics, photonics and photovoltaics due to their direct bandgap and excellent carrier mobility. Typically, these NWs are grown epitaxially on crystalline substrates, which could limit potential applications requiring high growth yield to be printable or transferable on amorphous and flexible substrates. Here, utilizing Ni as a catalytic seed, we successfully demonstrate the synthesis of highly crystalline, stoichiometric and dense GaAs NWs on amorphous SiO(2) substrates. Notably, the NWs are found to grow via the vapor-solid-solid (VSS) mechanism with non-spherical NiGa catalytic tips and low defect densities while exhibiting a narrow distribution of diameter (21.0 ± 3.9 nm) uniformly along the entire length of the NW (>10 µm). The NWs are then configured into field-effect transistors showing impressive electrical characteristics with I(ON)/I(OFF) > 10(3), which further demonstrates the purity and crystal quality of NWs obtained with this simple synthesis technique, compared to the conventional MBE or MOCVD grown GaAs NWs.
authors.affiliation: Department of Physics and Materials Science, City University of Hong Kong, 83 Tat Chee Avenue, Hong Kong SAR, People's Republic of China.
authors.forename: Ning
authors.initials: N
authors.lastname: Han
authors.forename: Fengyun
authors.initials: F
authors.lastname: Wang
authors.forename: Alvin T
authors.initials: AT
authors.lastname: Hui
authors.forename: Jared J
authors.initials: JJ
authors.lastname: Hou
authors.forename: Guangcun
authors.initials: G
authors.lastname: Shan
authors.forename: Fei
authors.initials: F
authors.lastname: Xiu
authors.forename: TakFu
authors.initials: T
authors.lastname: Hung
authors.forename: Johnny C
authors.initials: JC
authors.lastname: Ho