A comparison of in situ polishing and ion beam sputtering as surface preparation methods for XPS analysis of PVD coatings

Abstract XPS measurements have been performed on three coatings, TiN, TiAlN and MOST (MoS 2 +Ti), in which the surface oxide is removed by in situ UHV mechanical polishing. Examination of the XPS core level lineshape, before and after cleaning, shows in situ polishing to be a successful method of removing the surface oxide and exposing the bulk. A comparison of data obtained by RBS and XPS from both a mechanically polished surface and an ion beam cleaned surface demonstrate that mechanically cleaned surfaces gave reliable compositions. Severe preferential sputtering is observed for the MOST coating and mechanical polishing is shown to be an excellent method to prepare the coating for analysis by electron spectroscopic methods.