XPS ANALYSIS OF METAL GRAIN-BOUNDARY SURFACES

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