A large volume cylindrical radio frequency (rf) plasma source using a magnetic linehyphen;cusp field has been developed for use in large scale plasma processing. In this type of plasma source, a capacitively coupled 13.56 MHz rf plasma is produced in the presence of a magnetic linehyphen;cusp field. Three versions of the plasma source have been constructed and tested. The first version has a pair of peripheral rf electrodes placed outside the ionization chamber and is suitable for preparing a large volume uniform plasma. This plasma source can attain a useful area of plasma with 10percnt; uniformity over a 30hyphen;cmhyphen;diam region. The second version is featured by parallel doughnuthyphen;plate electrodes which form part of the chamber wall and serve as a high current source, where the electron density is proportional to the rf power, being equal to 4times;1010cmminus;3at 400 W. The third version is a slabhyphen;plasma source, which has a rectangular ionization chamber, a pair of rectangular magnetic coils, and a pair of rectangular rf electrodes, yielding an electron density of the order of 109cmminus;3for a 25 W rf power.
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