STRUCTURAL AND ELECTRONIC STUDIES OF CLEAN AND OXIDIZED THIN FE FILMS ON POLYCRYSTALLINE COPPER

The local structure of very thin films of iron, deposited in an ultrahigh vacuum (UHV) onto polycrystalline copper and submitted to oxidation and thermal treatments, has been studied by surface electron energy-loss fine structure (SEELFS) spectroscopy in reflection mode beyond the L2,3-edges of iron and the K-edge of oxygen. These results have been correlated to x-ray photoemission (XPS) measurements performed on the same samples. Our results can be summarized as follows: lowering of the lattice parameter of the iron deposit, supporting the hypothesis of a cluster growth; selectivity toward the oxidation process of the iron deposits with respect to the copper substrate; restoring the metallic behaviour of the iron deposit after thermal treatment.