D.J. O’Connor

Initial growth of ultrathin Pd films on Cu(001)

The submonolayer deposition of Pd on Cu(001) at room temperature (<50 °C) has been studied by low energy alkali ion scattering and low‐energy electron diffraction (LEED). The Cu(001)c(2×2)–Pd and Cu(001)p(2×2)‐p4g–Pd LEED patterns were observed at Pd coverage of 0.5 and 1.0 monolayers, respectively. The results of the azimuthal scans at grazing incidence showed evidence of surface alloying by the substitution of Cu with Pd atoms in the first layer even at very low coverages. This evidence was confirmed by observing Pd–Pd double scattering peak along the [100] azimuthal direction using 2 keV K+ ions. The structure of the Cu(001)c(2×2)–Pd surface alloy has also been probed by measuring the intensity of Li+ ion scattering as a function of the incidence angle along the mixed Cu and Pd rows. The results showed that the Pd atoms were coplanar with the Cu atoms in the topmost layer.