SCANNING TUNNELING MICROSCOPY AND PHOTOEMISSION FROM FE/CU(111)

Using scanning tunneling microscopy and angle-resolved uv photoemission, we have measured thin films of Fe on Cu(111) in the coverage range between 0.03 and 5 monolayers. Our results show that under the experimental conditions used (substrate temperature between room temperature and 300-degrees-C) the Fe deposit condenses in the form of three-dimensional islands. Only at the nucleation stage are two-dimensional Fe structures with monatomic height observed on the surface. Fe preferentially condenses at step edges on the upper terrace. We see indications of Fe-induced diffusion of Cu atoms already at room temperature. The shape of the Fe islands provides evidence for the growth of Fe islands in the form of fcc Fe(111) layers. The photoemission results exhibit distinct differences in the electronic states below the Fermi level for the 1-monolayer and 5-monolayer film, which, in our opinion, are representative of a thin fcc Fe(111) film and bulk fcc Fe(111), respectively.