Crater formation by single ions, cluster ions and ion showers

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS

卷:272

Article; Proceedings Paper

Djurabekova, Flyura^1,2  Samela, Juha^1,2  Timko, Helga^1,2,3  Nordlund, Kai^1,2  Calatroni, Sergio³  Taborelli, Mauro³  Wuensch, Walter³ 

[1] Helsinki Inst Phys, FI-00014 Helsinki, Finland

[2] Dept Phys, FI-00014 Helsinki, Finland

[3] CERN, CH-1211 Geneva 23, Switzerland

关键词: Molecular dynamics simulation;    Craters;    Plasma-wall interaction;   

DOI  :  10.1016/j.nimb.2011.01.104

来源: Elsevier

【 摘 要 】

The various craters formed by giant objects, macroscopic collisions and nanoscale impacts exhibit an intriguing resemblance in shapes. At the same time, the arc plasma built up in the presence of sufficiently high electric fields at close look causes very similar damage on the surfaces. Although the plasma-wall interaction is far from a single heavy ion impact over dense metal surfaces or the one of a cluster ion, the craters seen on metal surfaces after a plasma discharge make it possible to link this event to the known mechanisms of the crater formations. During the plasma discharge in a high electric field the surface is subject to high fluxes (similar to 10(25) cm(-2) s(-1)) of ions with roughly equal energies typically of the order of a few keV. To simulate such a process it is possible to use a cloud of ions of the same energy. In the present work we follow the effect of such a flux of ions impinging the surface in the shower manner, to find the transition between the different mechanisms of crater formation. We also introduce the shower-like regime of ion bombardment (underdense cloud of ions) as a subsequent regime between the single ion impact (a rare shower) and cluster ions (densely packed cloud). (C) 2011 Elsevier B.V. All rights reserved.

【 授权许可】

Free