PREFERENTIAL SPUTTERING ON THE SURFACE OF Ag-Pd ALLOY

Changes in the surface composition of Ag-Pd alloy under argon ion bombardment have been monitored by XPS. It is shown that the surface of the alloy isrich in Ag after annealing and is rich in Pd after ion bombardment due to their different surface binding energy. The component sputtering yield ratio S_(Ag)/S_(Pd) is obtained using Shimizu model. The experiment and its results are compared with that obtained by the other researchers. It is found that the yield ratio varies with the alloy composition, and is related to the disorder surface layer formed by argon ion bombardment. The yield ratio S_(Ag)/S_(Pd) of the Pd dilute alloy (X_(Pd)=0.32 at.-%) is much larger than that of the others.