LOW-TEMPERATURE DIAMOND GROWTH USING HALOGENATED HYDROCARBONS

We deposited CVD diamond films at substrate temperatures T-sub below 6 00 degrees C using halogen-containing precursor gases. CHF3 and C2H5Cl made possible a significant decrease in T-sub down to 370 degrees C u sing hot-filament CVD technique. At lower T-sub only amorph-graphitic depositions could be obtained. The lowest substrate temperature for di amond growth T-min depends on the deposition parameters. We find a dec rease in this temperature with decreasing carbon content in the precur sor gas or decreasing filament to substrate distance. These effects sh ow the influence of both surface diffusion and concentration of radica ls in the gas phase near the substrate.