Synthesis of nickel mono-silicide nanowire by chemical vapor deposition on nickel film: Role of surface nickel oxides

Abstract

We synthesized nickel mono-silicide nanowires (NiSi-NWs) on electron-beam-evaporated Ni films with SiH4/H2 gases in a chemical-vapordeposition chamber, and studied the growth mechanism of NiSi-NW by investigating various synthesis conditions. Results show that NiO and Ni 2O3 phases coexist on nickel surface and agglomerate after heating and the initial growth of NiSi-NW is triggered by the Ni 2O3. The effects of these surface nickel-oxides on NiSi-NW growth were investigated, and a synthesis model based-on vapor-liquid-solid mechanism with the aid of nickel diffusion to initiate NiSi-NW synthesis is proposed. It is also found that the diameter of NiSi-NW is mainly controlled by the synthesis temperature and the activation energy of NiSi-NW formation is estimated to be 1.72 eV. © 2009 The Japan Society of Applied Physics.