Chemical Vapor Deposition of TiSi Nanowires on C54 TiSi(2) Thin Film: An Amorphous Titanium Silicide Interlayer Assisted Nanowire Growth

Abstract

A C54-TiSi(2) film was grown on a Si substrate at 1073 K by low pressure chemical vapor deposition (LPCVD) employing titanium subchlorides TiCl(x)((g)), generated by reacting between TiCl(4(g)) and Ti((s)) at 1173 K, as the Ti source. Growth of titanium silicide (TiSi) nanowires (NWs; diameter 30-80 rim, length several micrometers) on a C54-TiSi(2) film was observed. Growth direction of the NWs was determined to be along the [010] axis. An amorphous titanium silicide interlayer was observed between the NWs and the C54-TiSi(2) film. This interlayer, probably existing as a quasi-liquid thin film during the growth, appears to be the key factor to assist the NW development. Field emission properties, turn-on field E(o) and field enhancement factor beta, of the vertically grown TiSi NWs were determined to be 5.25 V mu m(-1) and 876, respectively.