title: Fabrication of Ni-silicide/Si heterostructured nanowire arrays by glancing angle deposition and solid state reaction.
abstract: This work develops a method for growing Ni-silicide/Si heterostructured nanowire arrays by glancing angle Ni deposition and solid state reaction on ordered Si nanowire arrays. Samples of ordered Si nanowire arrays were fabricated by nanosphere lithography and metal-induced catalytic etching. Glancing angle Ni deposition deposited Ni only on the top of Si nanowires. When the annealing temperature was 500°C, a Ni3Si2 phase was formed at the apex of the nanowires. The phase of silicide at the Ni-silicide/Si interface depended on the diameter of the Si nanowires, such that epitaxial NiSi2 with a {111} facet was formed at the Ni-silicide/Si interface in Si nanowires with large diameter, and NiSi was formed in Si nanowires with small diameter. A mechanism that is based on flux divergence and a nucleation-limited reaction is proposed to explain this phenomenon of size-dependent phase formation.
authors.affiliation: Department of Materials Science and Engineering, National Chung Hsing University, Taichung 40227, Taiwan. hfhsu@dragon.nchu.edu.tw.
authors.forename: Hsun-Feng
authors.initials: HF
authors.lastname: Hsu
authors.forename: Wan-Ru
authors.initials: WR
authors.lastname: Huang
authors.forename: Ting-Hsuan
authors.initials: TH
authors.lastname: Chen
authors.forename: Hwang-Yuan
authors.initials: HY
authors.lastname: Wu
authors.forename: Chun-An
authors.initials: CA
authors.lastname: Chen