Preparation and characterization of well-ordered MoOx films on Cu3Au(1 0 0)–oxygen substrate (CAOS)

Abstract

5 p. : il.The goal of this work is to prepare well-ordered molybdenum oxide films using oxygen implanted Cu3Au(1 0 0) substrate (CAOS, Cu3Au– Oxygen Substrate) and identify the structure of the different oxide phases. Those films were grown on an UHV chamber (2 x 10=¹º mbar background pressure) and prepared by electron beam deposition. The structure of the films was studied using low energy electron diffraction (LEED), scanning tunnelling microscopy (STM), and X-ray photoelectron spectroscopy (XPS). The ultra thin molybdenum film shows the formation of an oxide layer with hexagonal symmetry plus a square lattice. The hexagonal mesh units are rotated by 908 (or 308) with respect to one another. Based on XPS data, the Mo cations are in an oxidation state that ranges from 4+ to 6+. STM results show the presence of hexagonal islands formed over a square symmetry phase