Scanning tunneling microscopy study of coverage-dependent morphology of Fe films on graphite

The morphology evolution of Fe films grown on highly oriented pyrolytic graphite (HOPG) has been studied depending on degree of covering by using scanning tunneling microscopy(STM). In the submonolayer regime the substrate step edges play a dominant role, however, by increasing the density of coverage the contribution of Fe nanoparticles grown on substrate terraces becomes more important. In low covering, size distribution of Fe nanoparticles grown on step edges is narrower. The results obtained are discussed taking into account the features of nucleation and growth of metal particles on HOPG. (author)