From LEED to MULSAM

Abstract

This account gives an outline of the work done in the Department of Physics, University of York since 1965. The Surface Physics Group has been particularly active in the development and application of electron probes of solid surfaces with strong emphasis upon low‐energy electron diffraction and scanning electron microscopy using Auger electrons to form images. A scanning Auger microscope using multi‐imaging (MULSAM) has been particularly fruitful for the study of a variety of heterogeneous materials. Examples are given of the application of MULSAM to the minimization of topographic contrast artefacts, to the study of multilayers of magnetic materials, to the characterization of very rough PtRh catalyst surfaces, to the interpretation of the shapes of electron spectra and to the angular dependence of both Auger electron and energy‐dispersive x‐ray signals. Copyright © 2000 John Wiley & Sons, Ltd.

Monte Carlo Simulation of SEM and SAM Images

“…However, the important mechanism of Auger signal contrast has not yet been discussed in detail. Furthermore, the interested specimens have been shifted from micrometer structure to nanometer structure (Childs et al, 1996) now with the instrumental improvement (Jacka, 2001;Prutton, 2000;Venables & Liu, 2005); it thus requires explanations for many effects appeared in the nano-systems. In this respect the image simulation can help us to comprehend the contrast formation mechanism and, therefore, is expected to play an important role for predicating the artifact and improving precision of elemental mapping by SAM.…”

Growth and trends in Auger-electron spectroscopy and x-ray photoelectron spectroscopy for surface analysis

“…61 Tougaard has developed software and procedures with which portions of a measured AES or XPS spectrum can be analyzed to give information on the sample morphology as well as the surface composition. [70][71][72][73] The sample morphology is also important in AES and XPS measurements of specimens with nonplanar surfaces ͑e.g., semiconductor wafers with deposited lines and other features, fine particles on a substrate, or dispersed catalysts on a support͒. This analysis indicates if the sample is homogeneous, if the composition is varying with depth, if the sample is layered, or if a surface phase consists of islands.…”