Ion-bombardment modification of surface morphology of solids. II: Changes in surface shape

Ion bombardment modification of surface geometrical structure, i.e. surface roughness alteration (Part I) and changes in surface shape (this paper) are considered. Two surface shape alteration methods, masked and maskless pattern etching, are described. They have been applied to modify various kinds of targets, including metals (99.9% aluminium and 99.9% titanium), metal alloys (stainless steel of 1H18N9T and SS316LC), alumina ceramic (96% Al sub 2 O sub 3 ) and Teflon. The results of experiments, where narrow beam glow discharge (GD) and broad beam Kaufman type guns have been used as ion sources, are presented. Approximation of a real surface shape profile by a so-called mean line, which is very helpful in the case of ion patterned but extremely rough surfaces, is also discussed. Finally, the practical aspects of ion bombardment modification of surface shape phenomenon, i.e. its application to sputtering yield and sputtering velocity measurements, are shown.