XPS studies on silicide formation in ion beam irradiated Au/Si system

X-ray photoelectron spectroscopic (XPS) studies were carried out on ion-beam irradiated Au/Si system. Thin films of Au (500 Angstrom) were vapour deposited on Si(111) and irradiated with 120 keV Ar+ ions at different temperatures. The XPS investigation showed the formation of gold silicide. Even in the case of the sample irradiated at room temperature silicide phase was observed at the top surface indicating the out-diffusion of silicon. Increase in the concentration of silicide phase at the top surface with increasing temperature of irradiation was observed suggesting higher out-diffusion of silicon at elevated irradiation temperature. The paper presents the results of the above study and proposes a simple model to explain the growth of the silicide phase. (C) 1997 Elsevier Science B.V.