The method of photoelectron spectroscopy is a modern method of investigation of occupied electronic states in solids. It is based on the phenomenon of the photoelectric effect: electron in a solid is optically excited by a photon to the unoccupied state. Photoelectron spectroscopy of core levels enables to obtain quantitative information about elemental and chemical composition of the surface area of the samples. Method of elemental mapping of surface is used for study elemental and chemical composition of samples with lateral resolution, the implementation of this method is possible due to the presence of special microchannel plate, which allows to analyze the emitted photoelectrons from a solid body with a spatial resolution.