title: Electron spectroscopy investigation of the oxidation of ultra-thin films of Ni and Cr on Fe(0 0 1).
abstract: We investigated the room temperature oxidation of ultra-thin Ni and Cr films grown on Fe(0 0 1). In particular, we characterized the degree of crystallinity and the stoichiometry of the oxide layers and addressed the chemical stability of the interface with the highly reactive Fe substrate by means of low-energy electron diffraction and x-ray and UV photoemission spectroscopy. In the Ni case we detected, upon oxidation, the formation of a Fe(3)O(4) layer covering the Ni oxide, due to the diffusion of Fe cations towards the surface. At high temperature and in ultra-high vacuum conditions, the Ni oxide dissolved and the Fe oxide layer was reduced to FeO. In the Cr case, we observed the formation of a thin Cr(2)O(3) oxide layer, showing a diffraction pattern compatible with a defective γ-Cr(2)O(3) phase. A thicker Cr oxide layer could be produced by oxidizing the sample at 300 °C, at the expense of the incorporation of trace amounts of Fe cations.
authors.forename: A
authors.initials: A
authors.lastname: Calloni
authors.forename: G
authors.initials: G
authors.lastname: Berti
authors.forename: A
authors.initials: A
authors.lastname: Brambilla
authors.forename: M
authors.initials: M
authors.lastname: Riva
authors.forename: A
authors.initials: A
authors.lastname: Picone
authors.forename: G
authors.initials: G
authors.lastname: Bussetti
authors.forename: M
authors.initials: M
authors.lastname: Finazzi
authors.forename: F
authors.initials: F
authors.lastname: Ciccacci
authors.forename: L
authors.initials: L
authors.lastname: Duò