Calculation of energy‐dependent photoionization probabilities for valence electrons in diamond and silicon crystals

Abstract
Photoionization probabilities for valence electrons in covalent semiconductor crystals are calculated in order to analyse the connection of the photoelectron spectra with the densities of valence electron states. A model is proposed and tested, which is based on solid state properties (adjusted sp3 tight binding functions and OPW functions are used for the initial and final states, respectively) and which yields purely energy‐dependent photoionization probabilities. Rather good results are obtained for C and Si; discrepancies occurring with Ge are discussed.