Gas-Jet Synthesis of Diamond Coatings from a H 2 +CH 4 +Ar Mixture Activated in a Microwave Discharge

In this study, a gas-jet diamond synthesis method using a high-speed jet for the transportation of gases activated in microwave plasma of gases to a substrate was developed. Diamond was synthesized in a hydrogen–methane–argon mixture. The diamond synthesis rate (130 µm/h) exceeded the rate attained in earlier gas-jet experiments with activation in microwave plasma without argon additions.