CH3OH CONCENTRATION AND TOTAL PRESSURE-DEPENDENCE OF DIAMOND FILMS FORMED FROM CH3OH-H2 MIXED-GAS BY MAGNET-ACTIVE MICROWAVE PLASMA CHEMICAL-VAPOR-DEPOSITION

Diamond films were deposited by a magnetic-field-assisted microwave plasma from CH3OH-H-2 mixed gas at the pressure range from 0.1 Torr to 0.5 Torr and a CH3OH concentration of 17-100%. CH3OH concentration and total pressure dependence of the diamond films were examined. We observed that the deposition rate decreased and the quality of diamond films improved as the total pressure and the CH3OH concentration increased. Secondary ion mass spectroscopic analysis showed that the diamond films contain hydrogen in a concentration greater than 5 x 10(19) cm-3. It Was observed from Raman spectra that the quality of diamond films is related to the hydrogen content of the diamond films. From the results of optical emission spectra, it was found that OH radical is related to the quality of the diamond films.