EFFECTS OF OXYGEN ADDED TO REAGENT GAS ON DIAMOND THIN-FILM GROWTH

The effects of oxygen addition on hydrogen-based CVD plasma for diamon d film synthesis were examined with respect to the gas phase. For plas ma diagnosis, plasma impedance measurement, which has the advantage of remote sensing (no plasma distortion) and real-time measurement, was introduced. Oxygen addition (0-5 seem) to the hydrogen plasma clearly changed the observed impedance value from nearly real resistive to sli ghtly reactive complexes on the Smith chart. Studies made under variou s plasma conditions and plasma emission measurements revealed that oxy gen addition increased plasma density, resulting in the enhancement of diamond growth from a viewpoint of gas phase as well as diamond surfa ce reaction.