ION SOURCES FOR ION-BEAM ASSISTED THIN-FILM DEPOSITION

Ion beam assisted deposition (IBAD) is a coating technique which combines a thin-film deposition method such as evaporation with irradiation by highly energetic ions from an ion source. Application of an ion source and a vapor source which are operated independently of each other render the IBAD technique highly controllable, reproducible, and flexible. Ion flux, atom flux, ion energy, ion impact angle, and other parameters can be controlled independently over a wide range. In order to take advantage of the beneficial features of this technique and obtain optimum process conditions ion sources with special properties are required. In this article different ion source types and equipment which has been used for IBAD to-date are presented and their special features discussed. Ion sources which should be applicable for IBAD are described. Finally, general requirements of IBAD ion sources are discussed.