XPS STUDY OF THE SURFACE ENRICHMENT PROCESS OF CARBON ON C-DOPED NI(111) USING INELASTIC BACKGROUND ANALYSIS

The surface segregation and precipitation mechanism of epitaxially grown graphite (0001) layers on the C-doped Ni(111) surface at various temperatures has been investigated by in-situ XPS measurements and inelastic-background analysis with the Tougaard method, From the C1s peak intensities as well as the C1s peak shifts as a function of temperature, we can identify three states corresponding to the presence of individual surface carbon atoms, monolayer graphite, and multilayer graphite. inelastic-background analysis of C1s, Ni3s, 3p, and the valence band energy regions was applied to the monolayer graphite and the growth of the surface-precipitated multilayer-graphite at 1015 K. The observed growth mode was island formation on the pre-existing monolayer graphite, that is, a kind of Stranski-Krastanov growth mode.