Depth profiling by X-ray photoelectron spectrometry

The present work describes depth profiling in the near surface region of solids by x-ray photoelectron spectrometry. The necessary method and the theoretical correlation between the experimental data and the complete evaluation is described. The influence of mean free path, the surface roughness, the solid angle of the cone of electron acceptance and the statistical scattering of experimental data on the reconstruction of the depth profiles has been investigated by computer simulations and examinations of silicon dioxide-films on silicon-wafers. In this work the segregation depending on temperature of polycrystalline Pt-Ni-alloy and on S in Fe was also examined. The heating of a polycrystalline Pt-Ni-sample to 600 deg C caused a process of segregation, which yields an enrichment of Pt in the near surface region. After cooling this condition was frozen in. A segregation of S in an iron- sample was observed at 550 deg C. The enrichment due to segregation is also stable after cooling. At the end we analyzed the depth profile of silicon dioxide and silicon nitrides on silicon-wafers by different X-ray excitations. (author)