The erosion of amorphous and crystalline surfaces by ion bombardment

Abstract

Ion etching is a commercially important technique used in the micromachining of solid surfaces. In this paper the three-dimensional theory of the development of surface topography during ion bombardment is extended to include the effects of surface crystallinity. The method of characteristics is used to trace the development of edges and facets that develop on three-dimensional surfaces due to multiple stationary points present in the angular dependence of the sputtering yield. The analytical approach used facilitates subsequent numerical calculations and examples are given to illustrate the applications of the theory to both amorphous and crystalline structures.