Simple microwave-produced plasma source for diamond thin film synthesis

Summary form only given. The authors describe a simple microwave-produced plasma source constructed for the plasma-assisted chemical vapor deposition of diamond thin films. The facility consists of a cylindrical stainless-steel vacuum vessel of dimensions 20 cm diameter by 13 cm long into which up to approximately 1 kW of 2.45 GHz microwave power is fed from an axial, flush-mounted cylindrical waveguide feed at one end. A H/sub 2CH/sub 4/ gas mix (approx. 99:1) is fed into the vessel to a pressure of about 50 Torr. Silicon substrates of 1-inch diameter are introduced into the vessel on a quartz pedestal and a well-defined plasma ball is produced above the substrate. The facility has been used for making diamond thin films of high quality, with crystallite size up to to 10 /spl mu/m. The research program is directed toward characterizing the plasma and quantifying its parameters as a function of the diamond thin films produced.