Materials sputtering by fission fragments

Experimental results on sputtering of different materials by heavy multiply-charged ions (fission fragments) are discussed. The data desribing sputtering coefficients as a function of different parameters as well as certain characteristics of the sputtered material are presented. It is noted, when specific ionization losses of heavy multiply-charged ions are > or approximately 1.3x104 eV/nm, two types of sputtering are supposed to take place. One type is found in the case of fine-grained materials with grain size < or approximately 20 nm; it is characterized by large K (103-104 at./fragm.) and mainly due to inelastic interactions of fission fragments with atoms of the material. The other type of sputtering is found for metals with larger grains (diameter > or approximately 50 nm) and non-conducting materials and characterized by relatively low K (5-50 at./fragm.); the relation and role of elastic and inelastic interactions of fission fragments with atoms of the substance in sputtering are still to be explained