SURFACE CLEANING USING SPUTTERING

In this article sputtering phenomena as related to the removal of contaminant layers from surfaces are reviewed. Basic relations for sputtering of adsorbed layers by ion bombardment and the corresponding cross sections are discussed in the introductory part. The following section presents models for the sputtering of overlayers with the intention of understanding the relevant physical processes and to obtain quantitative estimates. Subsequently, undesirable by-products of ion bombardment, such as surface damage, particle implantation and preferential sputtering are considered. A concise experimental section deals with ion beam and glow discharge techniques applied for surface cleaning as well as with some surface analytical methods (Auger electron spectroscopy, low-energy ion scattering, secondary ion mass spectroscopy) which are useful and necessary to check the obtained cleaning effect. In the final section various examples are given and some conclusions are drawn for the efficiency of surface cleaning by sputtering. © 1990 Springer-Verlag.