ROLE OF IONS IN REACTIVE ION ETCHING

Energetic ion bombardment is responsible for the anisotropic etching w hich can be obtained in reactive ion.etching. This has been recognized for many years but the detailed mechanisms involved in this process a re still not well understood. In this paper, the various phenomena res ulting from ion bombardment of a surface in a reactive gas glow discha rge will be summarized. The discussion will be limited to chemical dry etching environments, that is, the products of the reactive gas-surfa ce interaction are volatile at or slightly above room temperature. The phenomena which will be discussed are chemical sputtering, ion-induce d mixing, ions as a source of reactants, physical sputtering, and the effect of prior ion bombardment on selected gas-surface reactions.