Three-dimensional reactive-flow simulations of filament-assisted diamond deposition

Developed three dimensional (3D) model of a hot-filament CVD reactor is used to study the gas-phase and surface processes of diamond growth. Full set of transport equations including detailed gas-phase reaction mechanisms, molecular diffusion and thermodiffusion, catalytic hydrogen dissociation at the filament and surface kinetics at the substrate is numerically solved. The results of 3D and 2D model calculations are compared with experimental measurements of methyl, methane, acetylene and atomic hydrogen concentrations. Good quantitative and qualitative agreement of calculated species concentration distributions and known experimental data for different reactor parameters was obtained. An importance of 3D effects for the species densities and gas temperature distributions is revealed. Effects of reactor parameters variations are studied.