PREPARATION OF TEXTURED DIAMOND FILMS ON SI SUBSTRATES BY HOT-FILAMENT CHEMICAL-VAPOR-DEPOSITION

Diamond was deposited on Si(111) substrates by a two-step hot-filament chemical-vapor deposition method consisting of the pretreatment and growth processes. In the pretreatment process, the substrate was heated at 1473 K briefly in a C3H8-CH4-H-2 mixture gas. Textured [111]-oriented diamond films were obtained with nucleation density of 10(9) cm-2. SiC grains were formed along with the nucleation sites for diamond in the present pretreatment process. Diamond was not deposited on the SiC layer, which was intentionally formed on a Si substrate, using the present growth process. SiC formation is not a sufficient condition for diamond nucleation.