INITIAL-STAGE OF CU GROWTH ON SI(111)7X7 SURFACE STUDIED BY SCANNING-TUNNELING-MICROSCOPY

The initial stage of growth of Cu on Si(111)7 x 7 surface at room temperature is observed with a field ion-scanning tunneling microscope (FI-STM). Cu atoms adsorb on adatoms, especially center adatoms, as well as on rest atoms and some Cu atoms form small clusters at very low coverage. At submonolayer coverage triangular clusters lay on the center of sub-units of the DAS structure. At a higher coverage, nearly circular shaped islands are observed, which is a different shape than those observed by others.