The stability of equilibrium surface topography developed by sputtering

Previous publications have considered the development of topography upon isotropic, homogeneous solids resulting from the variation of erosion rate induced by energetic ion sputtering as a function of the angle of incidence of the ion flux. It has been shown that a steady state topography will develop after high fluence irradiation in certain circumstances, but except in the case of computational simulation the relative stability of the end forms has not been distinguished. In the present communication the stability criteria are explored. (U.K.)