Influence of resolution, escape depth, and defects on the line shape of 2$p$ spectra from the Si(100) surface

The results of quantitative and qualitative analysis of the fine structure of high-resolution (60 meV) 2$p$ spectra from the Si(100)c(4$\times$2) surface have been presented. The 2$p$ line is simulated for various photon energies, energy resolutions, and density of structural defects in the Si surface layer. The upper limits of the experimental parameters (photon energy and resolution), at which the characteristic features of the spectra can be used as an indicator of the surface quality, are established. The spectrum sensitivity to vacancies in the surface dimer layer is estimated. The obtained results can be used as reference data when conducting experiments and processing the results of photoelectron spectroscopy of the Si 2$p$ core level.