Atmospheric Pressure Chemical Vapour Deposition of TiCl4 and tBuAsH2 to Form Titanium Arsenide Thin Films

Titanium arsenide thin films were deposited by the atmospheric-pressure chemical vapour deposition (APCVD) of TiCl4 and tBuAsH(2) at substrate temperatures between 450 and 550 degrees C. The deposited films are typically silver in appearance, demonstrate good adherence and were identified by X-ray powder diffraction as crystalline TiAs. X-ray photoelectron spectroscopy (XPS) and Raman microscopy support the formation of TiAs. The TiAs films have an approximate 1:1 ratio of Ti:As, as identified by wavelength dispersive analysis of X-rays (WDX), and the films grow by an island growth mechanism with deposition rates of ca. 0.1 mu m min(-1). The films display borderline metallic/semiconductor conductivity and those deposited at 550 degrees C possess high hardness.