Growth of thin platinum films on Cu(1 0 0): CAICISS, XPS and LEED studies

Abstract

The growth mode of platinum films on the Cu(100) surface up to a coverage of 2.75ML has been studied using co-axial impact collision ion scattering spectroscopy (CAICISS), X-ray photoelectron spectroscopy and low energy electron diffraction. CAICISS data show the formation of a Cu–Pt alloy at room temperature in the top three atomic layers at sub-monolayer Pt coverage. As the coverage increases up to 2.75ML the formation of a Pt overlayer is observed in conjunction with the near surface region becoming Pt-rich, indicating the onset of layer-by-layer growth. Subsequent annealing shows a significant migration of Pt into the bulk Cu at a temperature of 300°C. Evidence for a more ordered surface after annealing is also presented.