The composition, structure, and physicochemical properties of the surface and near-surface layers of silicon doped with low-energy (E0<5 keV) Ba+ and O2+ ions have been studied using a set of photoelectron and secondary electron spectroscopy methods. It has been established that in the process of ion implantation, chemical bonds are formed between the atoms of the alloying element and the matrix, the width of the energy bands and the density of electronic states in the bands change.