Auger parameter studies of third-row chemical elements

摘要

The Auger parameter (AP) studies available in the literature are usually based on Auger transitions involving only core-level electrons. In this paper, besides the usual AP -alpha*(z) = [BE(2p)] + [KE(KL23L23)], (Z = third-row chemical elements) - we also considered the AP involving core - valence - valence Auger transitions -gamma*(z) = [BE(2p)] + [KE(L23VV)]. The chemical shifts for gamma* between Al-0 and Al2O3 and between Si-0 and SiO2 are more than twice that for alpha* whereas the difference in such chemical shifts progressively decreases with increasing Z. While the inelastic mean free path (lambda) associated with a* spans the range similar to 2.5-4.5 nm, gamma* relates to a much more surface-specific analysis, i.e. 0.5 < lambda < 2.5 nm. We discuss the diagnostic potential of gamma* and outline its advantages and shortcomings in the surface and interface analysis of materials. Copyright (C) 2006 John Wiley & Sons, Ltd.