Electron spectroscopy study of the Cu/SrTiO3(100) interface

Interface formation of copper on both reduced and stoichiometric SrTiO3(100) was investigated using photoemission (XPS, UPS), electron diffraction (LEED) and electron energy loss spectroscopy (HREELS). The growth mode of Cu on both surfaces involves the formation of a 2D-like layer and islands, but the thickness of the 2D-like layer and the number of islands is higher on the reduced substrate due to the higher number of defects. An analysis of the Auger parameter of Cu during growth demonstrates the strong interaction of Cu with SrTiO3. HREELS experiments showed a strong influence of the impact scattering interaction from the changes in the spectra with coverage, and the importance of the two different terminations of the (100) surface.