RECENT ADVANCEMENTS IN HIGH-INTENSITY HEAVY NEGATIVE-ION SOURCES BASED ON THE SPUTTER PRINCIPLE

Significant advancements have been recently made in the technology of forming high intensity heavy negative ion beams. Due to their ease of operation, simplicity, long lifetime, and wide range of species capabilities, negative ion sources predicated on the sputter principle are being used for an increasing number of diverse applications, including standard tandem accelerator-based research, high-energy ion implantation, tandem accelerator mass spectrometry, and low-energy atomic physics research. Sources have been developed which utilize either (1) direct surface ionization, or (2) a plasma to form the positive ion beam used to effect sputtering of samples containing the material of interest. This article will include a brief review of the fundamental processes underlying negative ion formation in these source. Emphasis will be placed on the descriptions and performance characteristics of specific sources based on each of the positive ion formation techniques. © 1990.