Diamond film deposited on a silica substrate with a ZnO:Al intermediate layer by hot-filament chemical vapor deposition

Diamond films were deposited on ZnO:Al thin-film silica substrates by hot-filament chemical vapor deposition. Ultrasonic irradiation in a diamond suspension enhanced the diamond nucleation density on a ZnO:Al-silica substrate. The nucleation density and the growth rate of diamond film deposited on ZnO:Al thin film is higher than on the silica. The cracks on a ZnO:Al-silica substrate occurred during the diamond deposition process. It is proposed that the cracks were caused by the stress in ZnO:Al film and diamond film, and the peak frequency shift of the Raman line of diamond indicates the presence of compressive stress in the diamond film.