Simulation and Analysis of Gas Phase Environment in HFCVD Diamond Films Growth

The paper simulated and analyzed gas phase environment in diamond films growth by hot filament chemical vapor deposition(HFCVD). GRI-Mech3.0, a detailed thermochemical reaction mechanism of methane combustion chemistry, was used to simulate C/H gas chemistry in HFCVD diamond films reactors. By simply simulating the reactive flow, the gas composition at the position of the substrate was obtained, which agrees well with other's experimental results. The influences of filament temperature, carbon-contained gas concentration and hydrocarbon precursor gases in feed on gas phase and diamond films growth were discussed. The results suggest that CH3 other than C2H2 is the dominant diamond films growth precursor in HFCVD, while H superequilibrium above substrate is important for good diamond films growth.