This Small Business Innovation Research Phase I project is to determine the feasibility of a novel turbine, forced convection reactor for high rate synthesis of diamond by chemical vapor deposition. The low growth rate of diamond by chemical vapor deposition (CVD) is the largest factor hindering the commercialization of CVD diamond products. Based on experimental and computer simulated results from a rotating substrate hot-filament assisted CVD reactor and an oxy-acetylene torch reactor, the rate of diamond growth is limited by the rate of mass transport of growth species to the diamond surface. Phase I work is aimed at demonstrating the feasibility of high rate diamond growth by increased mass transfer rates in a turbine, forced convection CVD reactor. The scope of this work includes: 1) designing and building a turbine, forced convection CVD reactor, and 2) performing experiments to demonstrate an order of magnitude increase in diamond growth rates. Increased mass transport, i.e., forced convection, will be achieved by using a turbine to pump process gas from the activation zone, i.e., the filament, to the substrate. Experiments will concentrate on both standard and non-standard conditions known by the proposer to grow good quality diamond. Computer modeling of the fluid mechanics and mass transport rates will support the experimental program. The proposed work will be performed by one full-time engineer at North Coast Crystals, Inc. and one subcontract by Case Western Reserve University to perform the computer modeling.
