XPS ANALYSIS OF METAL GRAIN-BOUNDARY SURFACES

X-ray photoelectron spectroscopy (XPS) can provide a quantitative analysis of the surface and determine the chemical state of elements present. However, until recently the spatial resolution has not been adequate to analyse small particles. As a result, Auger electron spectroscopy has been used to obtain elemental information where good spatial resolution is required. Analysis of grain boundary surfaces has therefore been restricted to this technique, with the result that no chemical-state information has been obtained relating to the elements present on the grain boundary. This paper describes results in which grain boundary surfaces exposed in an imaging XPS instrument have been analysed using XPS. In particular, tin and phosphorus are shown to segregate to the grain boundary surface in the elemental state.