Scaling laws for diamond chemical-vapor deposition. II. Atomic hydrogen transport

Scaling relations are developed to allow estimation of the atomic hydrogen concentration at the substrate during diamond chemical-vapor deposition for both diffusion-dominated and convection-dominated reactors. In the convection-dominated case, it is shown that there exists an optimal Mach number which maximizes the H concentration delivered to the substrate. In addition, when homogeneous recombination is taken into account, there exists an optimal operating pressure. This analysis shows that a sonic flow of highly dissociated hydrogen at a pressure near atmospheric is optimal for rapid growth of high-quality diamond.