Swift chemical sputtering of covalently bonded materials

Nordlund, K.; Salonen, E.; Krasheninnikov, A. V.; Keinonen, J.

doi:10.1351/pac200678061203

Pure Appl. Chem., 2006, Vol. 78, No. 6, pp. 1203-1211

http://dx.doi.org/10.1351/pac200678061203

Swift chemical sputtering of covalently bonded materials

K. Nordlund¹, E. Salonen², A. V. Krasheninnikov¹ and J. Keinonen¹

¹ Accelerator Laboratory, University of Helsinki, P.O. Box 43, FIN-00014 Helsinki, Finland
² Laboratory 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.