Measurement of the surface excitation probability of electrons reflected from Si surface

Silicon is the main material of nanotechnology and solar energy. In our days a lot of structures based on silicon have unique and useful properties which can help to deal with applied problems. One area of silicon application is the creation of silicon-based photovoltaic converters for space and aviation equipment. In the future, photovoltaic devices based on silicon can be made from the materials contained in the lunar soil, and silicon will form the basis for the development of space solar power. Control of the elemental composition and physical properties of materials used in space materials science plays an important role, accordingly necessary to improve the methods of research materials. The methods of research materials are developed both in technological direction and the direction of the processing and interpretation of experimental data. One of the widely used methods of surface investigation is electron spectroscopy. At the entrance and exit of the surface electrons generate surface excitations which share quantitative information on the various processes of interaction of electrons with matter. The intensities of Auger electron and photoelectron peaks depend both on the probability of inelastic scattering within the solid, and the surface layer. The probability of generating an electron surface excitations with a single act of interaction with the surface is called the surface excitation parameter that is the most convenient value to describe the effect of surface excitations on the intensity of the Auger electrons and plays an important role in quantitative analysis in Auger electron spectroscopy, X-ray photoelectron spectroscopy, electron energy loss spectroscopy. In this work energy loss spectra of reflected electrons were obtained for the series of samples of Si. Samples were obtained with different technical conditions and some of them have different crystallographic orientation. Energy loss dependence of inelastic mean free path and differential inelastic electron scattering cross-section were calculated. We have suggested a new method of determination of surface excitation parameter, based on fitting of these spectra with the Tougaard’s Three-parameter Universal cross-section.