Studies of steam-oxidized WSi2 by Auger sputter profiling

Abstract

We have studied steam‐oxidized WSi₂ films sputter deposited upon Si and SiO₂ substrates using Auger sputter profiling. As previously reported, steam oxidation produces an SiO₂ surface layer. Silicon is supplied to the growing SiO₂ layer by the conversion of the WSi₂ to W₅Si₃, and additional Si is supplied by diffusion through the WSi₂ layer only for the case of a Si substrate. The W₅Si₃ is distributed throughout the silicide layer, but with slightly higher concentration at the SiO₂‐silicide interface. This interface also contains an oxidized tungsten phase possibily is the form of a W_xSi_yO_z compound.