Factor analysis and XPS-data preprocessing for non-conducting samples

The use of factor analysis for automatic interpretation of electron spectra needs in some cases a special data preprocessing. It was shown for x-ray p hotoelectron spectroscopy that in the case of non-conducting samples in add ition to experimental methods (low energy electron flooding) a shift of the measured spectra with respect to a reference peak was useful. Thus, the re sidual energy shift due to sample charging, especially if the surface condu ctivity changes during measurement, could be removed. Several shift methods and the influence of different reference peaks were discussed.