THE CU/AL2O3/AL(111) INTERFACE - INITIAL FILM GROWTH AND THERMALLY INDUCED DIFFUSION OF COPPER INTO THE BULK

High-resolution electron energy loss spectroscopy and Auger electron spectroscopy have been used to investigate the Cu/Al2O3/Al(111) interface at temperatures between 95 and 700 K. The copper overlayer was deposited by in situ evaporation, and the Al2O3 substrate was prepared by controlled oxidation of an atomically clean AI(Ill) surface. It was found that the first monolayer of copper forms a smooth overlayer on the Al2O3/Al(111) substrate at 95 K. Heating the Cu/Al2O3/Al(111) layer causes an inward diffusion of the copper overlayer. The chemisorption of CO on the Cu/Al2O3/Al(111) substrate has been studied also and the results are compared to previous investigations of a Ni/Al2O3/Al(111) interface.