材料期刊网

Evolutions of angular distributions and surface composition profiles of a sputtered Pt0.5Cu0.5 alloy were simulated under 1 keV Ar ion bombardment at normal incidence, with the help of a dynamic Monte Carlo program including preferential sputtering and BIGS (bombardment-induced Gibbsian segregation) processes etc. It is found during the PtCu alloy sputtering that the Cu enrichment in the near-normal direction is regularly transformed into the Pt one as the Ar ion fluence increases. Below a low fluence of about 1.7 ions/cm2, Cu is preferentially ejected in the near-normal direction; above 1.7 ions/cm2, on the other hand, Pt is preferentially ejected in the near-normal direction instead of Cu. Effects of preferential sputtering and BIGS processes on enrichment transformation between Cu and Pt elements in the near-normal direction are also discussed.