Surface excitations in electron backscattering from silicon surfaces

Surface excitation effects in surface-sensitive electron spectroscopy (XPS, AES, EPES, EELS) influence substantially the measured peak intensities or peak areas. To obtain reliable quantitative information from the electron spectra, the measured intensities should be corrected for these effects. For this purpose, Chen has suggested a simple procedure based on the knowledge of the surface excitation parameter, SEP. The SEP depends on electron energy, the impact and the emission angle of electrons, and a material studied. The SEP can be calculated from the theory or it can be obtained semi-empirically. In this contribution, we compare both procedures. They are applied on measured electron backscattering probabilities from silicon surface with respect to copper and gold standards. Corrected peak areas are finally used for evaluating of inelastic mean free paths for silicon, and compared with the available literature data. Results show that the semi-empirical approach to the SEPs leads to a better agreement with the predicted behavior.