Pure Appl. Chem., 2006, Vol. 78, No. 6, pp. 1203-1211
doi:10.1351/pac200678061203
Swift chemical sputtering of covalently bonded materials*
K. Nordlund1, E. Salonen2, A. V. Krasheninnikov1, and J. Keinonen1
1Accelerator Laboratory, University of Helsinki, P.O. Box 43, FIN-00014 Helsinki, Finland; 2Laboratory of Physics and Helsinki Institute of Physics, P.O. Box 1100, FIN-02015 HUT, Helsinki, Finland
Abstract:
Numerous experiments have shown that low-energy H ions and neutrals can erode amorphous carbon at ion energies of 1-10 eV, where physical sputtering is impossible, but at erosion rates which are clearly higher than those caused by thermal ions. In this paper, we will first review our computer simulation work providing an atom-level mechanism for how this erosion occurs, and then present some new results for H and He bombardment of tungsten carbide and amorphous hydrogenated silicon (a-Si:H), which indicate the mechanism can be of importance in a wide range of covalently bonded materials. We also discuss how the presented mechanism relates to previously described abstraction and etching mechanisms.
Keywords: bond breaking; covalently bonded materials; erosion; plasma-surface interactions; sputtering.
*Paper presented at the 17th International Symposium on Plasma Chemistry (ISPC 17), Toronto, Ontario, Canada, 7-12 August 2005. Other presentations are published in this issue, pp. 1093-1298.