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A method of the non-destructive layer-by-layer analysis of the surface alloys composition is developed. It is based on the registration dependence of the intensities ionization lines (Ionization Spectroscopy) of components on the primary electron energy with following reconstruction layer-by-layer information by numerical mathematic methods. Ionization Spectroscopy (IS) is one of varieties of Electron Energy Loss Spectroscopy (EELS). The position of ionization line in the EELS spectra with respect to the primary electron energy E0 is determined by the binding energy of electrons in the internal state and by the distribution of the density of empty states, but it does not depend on the value of E0, on the work function or on the value of the surface charge. One important advantage of the IS method over other methods of electronic spectroscopy is the possibility to vary the probing depth by varying primary energy E0. The method of Ionization Spectroscopy was tested by measuring the concentration depth profiles with monolayer resolution in the near surface region of ordering single crystals alloys: Pt80Co20 faces (100) and (111), Cu75Pd25(100), FeNi3(111). The normalization using an external standard made possible to take account of instrumental factor, effect of ionization cross-sections, elastic scattering factors of electrons, as also possible matrix and diffraction effects are shown. For examples, a study temperature depth profiles concentration for alloys Pt80Co20(111) and FeNi3(111) is illustrated. |