Sputtering process during ion implantation in glasses: mathematical and physical analysis

Previously reported experimental results on Na depletion in the surface region of 50 keV Ar-implanted soda-lime silica glass have been interpreted on the basis of preferential sputtering of Na. A phenomenological model which accounts for the preferential ejection of Na atoms from the surface, and for the enhanced diffusion over the range of Ar, explains the experimental data very well. The model is also consistent with experimental results obtained in other laboratories.