Growth and characterization of nonstoichiometric magnetite Fe3-delta-O4 thin films

Epitaxial thin films of magnetite, Fe3-deltaO4, were produced by evaporating natural Fe or the Mossbauer active isotope Fe-57 onto MgO(100) substrates, with simultaneous oxidization of the iron film by a controlled NO2 flux. RHEED intensity oscillations show that the growth proceeds in a layer-by-layer fashion. Mossbauer spectroscopy was used to determine the conditions under which stoichiometric and non-stoichiometric magnetite thin films can be obtained. Furthermore, we report on a p(1 X 1) reconstruction of the Fe3O4(001) surface, which has not been observed before for epitaxial thin films of magnetite.