MICROROUGHNESS INDUCED ON SOLIDS BY ION-BOMBARDMENT .1. EXPERIMENTAL RESULTS ON SPUTTERING OF ALUMINUM BY A+(15 KEV) - QUANTIFICATION OF MICROROUGHNESS

Microroughness induced by ion bombardment of poly crystalline aluminium with A+ ions (15 keV) is studied versus erosion time (depth). A microroughness profile is recorded by displacement of a stylus at the bottom of craters with a commercial Perthen profilometer. A new method to quantify the results is proposed. The distribution of the number of eroded points at a given depth referred to an initial flat surface can be described by a Gaussian function around a mean eroded depth Z̄, with a microroughness index" σ(Z). The mean erosion rate ( Z ̄ in nm s) can be deduced for aluminium which surface is flooded or not with oxygen. The importance of the initial microroughness of the sample on the results is emphasized. © 1979."