Photoelectron signal simulation from textured samples covered by a thin film

In this paper we propose a mathematical model for calculating the XPS inten sity distribution from textured sample surfaces covered with a thin film. T he surface roughness is approximated using triangular prisms. Analytical ex pressions for calculation of the angular photoelectron intensity distributi on are given. The obtained results allow an understanding of the relation b etween the escape depths of emitted photoelectrons and the angular XPS inte nsity distribution. The results show that the X-ray photoelectron signals v ary significantly with a change in surface overlayer thickness and prism sl ope angle alpha. The maximum of the XPS intensity distribution does not cor respond to the maximum escape depth of emitted photoelectrons. The ejected photoelectron ejection angle characterizes the maximum location depth of th e investigated component or chemical bond. This model is useful when evalua ting the surface roughness and the film thickness. (C) 2001 Elsevier Scienc e Ltd. All rights reserved.