Studies of Correlations between Surface Composition Changes and Ion Bombardment Fluences of Multicomponent Materials

Liping ZHENG Xiqing XIA Mingyao LI Shanghai Institute of Nuclear Research,Academia Sinca,Shanghai,201800,ChinaRisheng LI Lab.of Atomic Imaging of Solids,Institute of Metal Research,Academia Sinica,Shenyang,110015,China

摘 要：<正> Correlations between surface composition changes and ion bombardment fluences were studied formulticomponent materials by using a dynamic Monte Carlo program,including the preferentialsputtering and bombardment-induced Gibbsian segregation （BIGS） processes.For the case of1 keV KR-¹⁰B_0.02¹¹B_0.08 （the most simple multicomponent material system）,it is found that the ¹⁰Bcomposition enriches at the surface at low fluences but depletes at the surface at high fluences.Forthe case of 1 keV Ar-Pt_0.5Cu_0.5.it is found that the Cu composition at the topmost surface is alwaysunder the bulk composition between zero and high fluences,but the evident composition gradient ofCu（the segregation species） exists in the surface at low fluences.The effects of the preferentialsputtering and BIGS processes on above two surface composition profiles are also discussed.

关键词：