Chemical and spectroscopic studies of metal oxide surfaces

Thin oxide films ~e.g., 5–10 nm of SiO2, Al2O3, NiO, MgO! supported on a refractory metal substrate ~e.g., Mo, W, Ta, Re! have been prepared by deposition of the oxide metal precursor in a background of oxygen. The thin-film nature of these samples facilitates investigation by an array of surface techniques, many of which cannot be effectively utilized on the corresponding bulk oxide. The structural, electronic, and chemical properties of these films have been studied with temperature programmed desorption, Auger electron spectroscopy, X-ray photoelectron spectroscopy, ion scattering spectroscopy, high resolution electron energy loss spectroscopy, and infrared reflection absorption spectroscopy. The results of these studies demonstrate the viability of using thin oxide films as models for the corresponding bulk oxide. © 1996 American Vacuum Society.