Emission Spectroscopy for Hot Filament Diamond Growth Process with Positive Substrate Biasing

Optical emission spectrum has been successfully measured on a hot filament diamond growth process with substrate biasing. The emission lines of atomic hydrogen, H₂, CH and CH⁺ were observed. Effects of methane concentration on the emission intensity of observed lines were systematically studied. The experimental results suggest that atomic hydrogen and CH⁺ radicals play an important role in diamond growth, while CH radical facilitates the formation of amorphous carbon.