NE+ AND AR+ ION BOMBARDMENT-INDUCED TOPOGRAPHY ON SI

The topographic evolution of Si irradiated at room temperature with Ne+ and Ar+ ions in the energy range 5-40 keV at 45 degrees to the substrate normal has been studied. Other than isolated etch pits, no topography results from Ne+ bombardment at all energies and from Ar+ bombardment at 5 and 10 keV. Argon ion bombardment at 20 keV, however, initially produces transverse low-amplitude waves that transform, with increasing erosion, into larger amplitude, corrugated and faceted, wave-like structures. The present data do not conform to existing model predictions but do suggest that light low-energy inert gas ions can be used to inhibit roughening during sputtering erosion.