Electronic properties of metal/MgO(001) interfaces

The Schottky barrier heights (SBH) at various metal-MgO interfaces (Mg, Al, Ni, Fe, Pd, and Ag) were studied by ultraviolet and X-ray photoelectron spectroscopy (UPS and XPS). In order to determine the Schottky barrier height, the energy distance between the O2s core level of MgO and the MgO valence band maximum (VBM) is determined to be 18.0 +/- 0.1 eV at first. The Schottky barrier heights variation with metal Pauling electronegativities is linear fitted with a slope parameter of 1.86 +/- 0.15.