Extraction of high current Cr ion beam from a multicusp metal ion source.

Improvements have been made in a metal ion source, which made it possible to produce high density metal vapor plasma for extracting high current metal ion beams. Experiments of chromium ion beam extraction were performed. The ion beam current reached 250 mA at the extraction voltage of 36 kV. Furthermore, stable operation was achieved at the extracted current of 117 mA. The temporal drift of ion beam current was within ±1% for 1 h. [ABSTRACT FROM AUTHOR]