THIN-FILM GROWTH ON AN O-PRECOVERED RU(0001) SURFACE

The growth of Cu on an O-precovered Ru(0001) surface was studied at various substrate temperatures by Auger electron spectroscopy, thermal desorption spectroscopy and sputter profiling. In contrast to the Volmer-Weber growth mode of Au films on O-precovered Ru(0001) the initial growth of Cu films is layer-by-layer at moderate temperatures (300 K-450 K). During the deposition of Cu, O is displaced from the Ru surface and transported to the top of the surface of the growing film. This can be observed up to Cu coverages of 9 ML and even higher, independently of the evaporation rate and substrate temperature. The thermal deposition spectra of Cu and O2 indicate the existence of an oxidized Cu layer.