Study of V/TiO₂ interface by X-ray Photoelectron Spectroscopy

The V/TiO₂ interface has been studied by the technique of x-ray photoelectron spectroscopy (XPS). Thin films of titanium were deposited on a quartz substrate and oxidized in situ to form TiO₂ overlayer. Thin films of vanadium were then deposited onto this TiO₂ substrate. The samples were annealed at 100, 200, 300, 400, and 500°C for fifteen minutes and were analyzed in situ by XPS. The titanium 2p, the vanadium 2p and the oxygen 1s core level analyzed for this purpose. The aluminum x-rays (energy = 1486.6 eV) were used as the source of excitation. The spectral data have been recorded at 45 degree take-off angle. The spectral data have been analyzed to estimate the chemical reactivity at the V/TiO₂ interface. The spectral features (shift in the core levels and the shape of the core level peaks) have been utilized. The chemical reactivity as a function of the thickness of the vanadium overlayer and the annealing temperature has been established and will be presented.