9615706 Sitar The proposed project will study heteroepitaxial nucleation and growth of diamond films on nickel (Ni) metal substrates via hot filament chemical vapor deposition. The goal of this research is to produce high quality, single crystal diamond films up to an area of l x l square centimeter on Ni substrates by using a novel chemical vapor deposition (CVD) process involving seeding, annealing, solution treatment, nucleation, and deposition. This multi-step CVD technique has recently been demonstrated to be very effective in suppressing graphite formation and promoting oriented diamond nucleation and growth on Ni substrates. The issues which will be investigated in this proposal include: solubility of carbon in presence of atomic hydrogen, effect of atomic hydrogen on the eutectic temperature; developing effective seeding techniques; optimizing the multi-step deposition process; promoting desired growth orientations; and performing detailed in-vacuo surface characterization and modeling of the nucleation and growth process. %%% The proposed research integrates state-of-the-art equipment and experienced personnel to conduct forefront research in the field of diamond science and technology. It will develop and expand our current knowledge base of diamond growth and enhance the ability to transfer a technological development out of the laboratory stage into useful industrial applications. The successful implementation of this program will greatly advance this vital diamond technology and help the U. S. enjoy continuing global leadership in this important research area. ***
