Oscillations of step velocity at sputtering of Si(111) vicinal surfaces by low-energy Xe ions

Abstract

The evolution of a vicinal Si(111) surface at layer-by-layer sputtering by low-energy Xe ion irradiation is simulated at various temperatures (500–650°C) and ion fluxes (10 12–6 × 10 12 cm −2 s −1). The spatial distribution of ion-induced surface defects was found to be responsible for the oscillations of step velocity and surface coverage at some temperature range depending on the ion-bean flux. The period of oscillations is defined by the time needed for the removal of one monolayer. The oscillations damp out when the steady state of the surface is reached.