SURFACE MORPHOLOGICAL-CHANGES INDUCED BY NARROW BEAM BOMBARDMENT

Samples of chromium-nickel stainless steel, tantalum, titanium and alumina ceramic were subjected to ion sputtering by narrow beam bombardment. The gun used in these experiments utilizes a cold-cathode glow discharge as the source of positive ions. Roughness measurements were performed to assess the surface morphological changes induced by the bombardment. The results suggest that ion sputtering is dominated by sequences of collisions occuring in the first surface layers. Shadowing effects also occurred and should be considered in this case.