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Reports on the development of ion sources for implantation application. Bernas ion source; Electron cyclotron resonance (ECR) ion source; Typical lifetime of the Bernas source; Wide range beam current controllability; Lifetime of the ECR source; Requirements of ion source for implantation application.

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]

A metal ion source has been developed for extracting high current ion beams of high melting point metals. In the discharge chamber, metal vapor was confined in high-temperature shields, and the pure metal plasma was produced by the arc discharge. In order to prevent the vapor deposits, the extraction electrodes were also required to be high temperature. Thus, multislit electrodes were improved to maintain fine beam optics even if they were heated. To investigate the metal ion extraction characteristics, Al ion beams were extracted and compared with Ar ion beams. Furthermore, high current Al, Cr, Si, and Ti ion beams were extracted, and the extracted current > 100 mA was obtained for each metal. [ABSTRACT FROM AUTHOR]

Ion Charge state and impurities extracted from a multicusp ion source have been studied with the use of a magnetic momentum mass analyzer. Impurities contained in high current metal ion beams are crucible materials (such as A1[sub 2]O[sub 3], BN, Y[sub 2]O[sub 3], C) and high melting point materials (such as Mo, Ta, W). To reduce these impurities, the dependence of the impurity on the arc discharge voltage has been investigated experimentally. Amounts of impurities and multicharged ions are decreased with arc discharge voltage. For example, at the are discharge voltage of 60 V, aluminum ion beam contains 1% impurities and 4% multicharged ions, and at the are discharge voltage of 20 V, impurities and multicharged ions are less than 1% in all. High-purity single-charged metal ion beams have been obtained. [ABSTRACT FROM AUTHOR]