INTERFACIAL LAYER EFFECTS IN THE GROWTH OF CVD DIAMOND

A comparative study of the formation of interfacial layers in the growth of diamond films was performed. Polycrystalline diamond films were grown on silicon and molybdenum substrates by two different methods: hot-filament and microwave-assisted chemical vapor deposition (CVD). Several sets of samples were prepared with increasingly short deposition times in order to investigate the early stages of growth. Silicon carbide and molybdenum carbide were the diamond film substrate layers observed and their morphology, structure and composition were analyzed by different characterization techniques. Thicker and better-defined interfacial layers were found in films grown by hot-filament CVD than in those obtained by microwave CVD with the same deposition conditions. An increase in the amount of silicon carbide caused an increase in the delay time observed in the onset of diamond film growth.