A photoemission investigation of deposition rate dependent growth of europium on silver films

Abstract

Europium overlayers on a polycrystalline silver substrate have been studied by X-ray photoelectron spectroscopy. Eu was deposited at rates of 0.4 Å/min and 0.8 Å/min. Ag 3d emission attenuation profiles show a distinct dependence on Eu evaporation rates. Sizeable Ag core level shifts upon deposition of Eu indicate that Eu and Ag react to form an interface alloy. A tendency of clustering at the surface of Eu is also argued to be present. The higher deposition rate is found to favor layer-by-layer growth, whereas the lower rate favors clustering or island formation.