VACUUM-ARC ION SOURCES - SOME VACUUM-ARC BASICS AND RECENT RESULTS

Vacuum arc ion sources have been developed and used in a growing number of laboratories around the world. Primary applications of this high current metal ion source have evolved for metallurgical ion implantation and for accelerator injection. Novel source versions and features have been developed, including an electronically switchable ''partitioned cathode'' whereby the metal species generated can be switched from pulse to pulse, a combined metal/gaseous source with a long lasting trigger, a low energy (approximately 1 keV) miniature source version, and a broad beam (50 cm diam extractor) multicathode version. Progress has been made also in characterization and manipulation of the plasma prior to extraction, e.g., in the understanding of the ion charge states produced and the development of macroparticle-removing magnetic filters. Advances in vacuum arc ion source design and operation have been accompanied by a deeper understanding of plasma production in vacuum arc cathode spots, and several features of vacuum arc ion sources can be explained by the specifics of ion formation within the spots. Here we present a short overview of some fundamental vacuum arc processes and examine some of the recent developments in vacuum arc ion source design and application.