Background removal in surface electron spectroscopy: Influence of surface excitations

A deconvolution formula has been derived for the background subtraction of electron spectra by including the effect of surface excitations into the Landau formula. With this formula the primary x-ray photoelectron spectroscopy spectra of Cu, Ag, and Au are calculated from the experimental data. The primary excitation spectra are compared to the results derived by Tougaard's method in which surface effects were neglected. In all cases studied the present result is markedly different from Tougarrd's result which has a tail extending similar to 50 eV below the peak. It is found that the tail can be essentially removed when surface excitations are considered. In conclusion, the large tail which occurred in Tougaard's results is not part of the primary excitation spectrum but may be due to inelastically scattered electrons caused by surface excitations.