Evaluation of the resonant mode behaviour of a compact, end feed, microwave plasma source

Summary form only given. Investigations of a small end excited microwave ECR plasma source have uncovered cavity resonances in the operational parameter space that are not fully explained by existing theory. One of the resonances involves the TE/sub 111/ cylindrical cavity mode excitation. However, the other resonance involves TM-like or TEM-like excitation. The plasma source in this investigation consists of: microwave applicator, quartz discharge chamber, and ECR magnet array. The microwave applicator is a cylindrical stainless steel microwave cavity, of 9.8 cm inner diameter. The cavity is internally tuned, by the adjustment of: 1) a sliding short, and 2) an adjustable end feed loop. The cylindrical quartz discharge chamber has an inner diameter of 70 mm and height of 56 mm. An eight pole 45 MGO permanent magnet array is placed around the circumference of the discharge chamber. This ERC source is operable over a range of power from 50 Watts to 300 W and a range of pressures from 0.5 mtorr to 100 mtorr.