ABSTRACT

This entry reviews the basic science of plasmas containing negative ions, dust particles, or both, with emphasis on the technologies used for the manufacture of semiconductor electronics. A brief introduction to plasma processing is given in the “Introduction” followed by a description of the most widely used devices both in the fabrication industry and in research laboratories dedicated to understanding and improving these processes. The basic physics of negative ion production in plasmas and a discussion of the effects of negative ions on the plasma are presented. Some applications of negative ion plasmas are discussed. The physics of plasmas containing charged dust particles, dusty plasmas, is presented. Due to the central role of the dust charge, a detailed description of dust charging is presented. A description of some of the important forces acting on dust particles is given. The specific issues arising in plasmas containing both negative ions and dust are then addressed. The devices used for etching of semiconductor materials contain negative ions formed from reactive gases. The negative ions are precursors for the formation of dust particles, which can grow in the plasma to micron sizes. The entry closes with some remarks concerning the near-term challenges faced by the plasma processing industry, as well as an outlook into promising new technologies and novel applications of low-temperature plasmas.