THEORETICAL AUGER SPECTROSCOPY OF SOLIDS: CALCULATION OF ENERGY PARAMETERS

Abstract

The Auger electron spectroscopy is an effective method to study the chemical composition of solid surfaces and near-surface layers. Sensing the Auger spectra in atomic systems and solids gives the important data for the whole number of scientific and technological applications. When considering the method principles, the main attention is given as a rule to the models for drawing chemical information from the Auger spectra and to the surface composition determination methods by the Auger spectrum decoding. It is just the two-step model that is used most widely when calculating the Auger decay characteristics. The relaxation processes due to Coulomb interaction between electrons and resulting in the electron distribution in the vacancy field have no time to be over prior to the transition. In this paper the combined relativistic energy approach and relativistic many-body perturbation theory with the zeroth order density functional approximation is applied to determination of the energy and spectral parameters of the Auger decay for the Na, Si, Ge, Ag solids. The results are compared with reported experimental results as well as with those obtained by alternative theoretical schemes. The important point is linked with an accurate accounting for the complex exchange-correlation (polarization) effect contributions and using the optimized one-quasiparticle representation in the relativistic many-body perturbation theory zeroth approximation, which significantly affects the agreement of theory and experiment.