SYNTHESIS OF DIAMOND USING RF MAGNETRON METHANOL PLASMA CHEMICAL-VAPOR-DEPOSITION ASSISTED BY HYDROGEN RADICAL INJECTION

A new plasma chemical vapor deposition (P-CVD) system was developed fo r synthesis of diamond. This system consisted of a parallel-plate radi o frequency (RF) (13.56 MHz) plasma reactor, with a radical source usi ng a microwave (2.45 GHz) discharge plasma and substrate heating using a cw-CO2 laser. In this system, hydrogen (H) radicals were generated in the microwave Ha plasma and preferentially injected near the substr ate in the parallel-plate RF magnetron methanol(CH3OH) plasma region. By scanning electron microscope (SEM) and X-ray diffraction (XRD) anal yses, it was found that diamond was successfully synthesized using thi s system. The effects of H radical on the diamond formation were also investigated from the results of optical emission measurements in the RF plasma region, thin-film deposition and etching of the nondiamond p hases by varying amounts of H radical injection.