文章基本信息

标题：Energy deposition by heavy ions: Additivity of kinetic and potential energy contributions in hillock formation on CaF2
本地全文：下载
作者：Y. Y. Wang ; C. Grygiel ; C. Dufour 等
期刊名称：Scientific Reports
电子版ISSN：2045-2322
出版年度：2015
卷号：4
期号：1
DOI：10.1038/srep05742
语种：English
出版社：Springer Nature
摘要：Modification of surface and bulk properties of solids by irradiation with ion beams is a widely used technique with many applications in material science. In this study, we show that nano-hillocks on CaF₂ crystal surfaces can be formed by individual impact of medium energy (3 and 5 MeV) highly charged ions (Xe²²⁺ to Xe³⁰⁺) as well as swift (kinetic energies between 12 and 58 MeV) heavy xenon ions. For very slow highly charged ions the appearance of hillocks is known to be linked to a threshold in potential energy (E_p) while for swift heavy ions a minimum electronic energy loss per unit length (S_e) is necessary. With our results we bridge the gap between these two extreme cases and demonstrate, that with increasing energy deposition via S_e the E_p-threshold for hillock production can be lowered substantially. Surprisingly, both mechanisms of energy deposition in the target surface seem to contribute in an additive way, which can be visualized in a phase diagram. We show that the inelastic thermal spike model, originally developed to describe such material modifications for swift heavy ions, can be extended to the case where both kinetic and potential energies are deposited into the surface.