Preparation, characterization, and chemical properties of ultrathin MgO films on Mo(100)

Abstract

Ultrathin MgO films have been synthesized under ultrahigh vacuum conditions by evaporating Mg onto Mo(100) in various background pressures of oxygen. Low-energy electron diffraction and surface spectroscopic studies show that the MgO films, prepared under optimum oxidation conditions, grow epitaxially in the 200–600 K substrate temperature range and have an essentially one-to-one stoichiometry. The nature of the near-surface defects of the MgO films grown at low oxygen pressures has been explored using electron energy-loss spectroscopy. Finally, the chemical properties of the stoichiometric MgO films have been investigated using high-resolution electron energy-loss spectroscopy.