Effects of H, OH, and CH3 radicals on diamond film formation in parallel-plate radio frequency plasma reactor

Diamond films were successfully synthesized in both parallel-plate radio frequency ~rf: 13.56 MHz! CH4 and CH3OH plasmas with injection of H and OH radicals generated in the remote microwave ~2.45 GHz! H2 /H2O plasma. Effects of H, OH, and CH3 radicals on the diamond film formation in the rf plasma reactor were investigated by the formation of diamond films employing radical injection technique and the measurement of density in the plasma. Under the condition of diamond film formation, CH3 density was measured by infrared diode laser absorption spectroscopy ~IRLAS!. The kinetics of CH3 in rf CH4 and CH3OH plasmas with injection of H and OH radicals were evaluated from the results of optical emission spectroscopy and lifetime of CH3 radicals estimated by IRLAS. © 1997 American Institute of Physics. @S0021-8979~97!06419-0#