Synthesis of ultrathin diamond film on fused silica substrate

A technique of ultrasonic surface pretreatment in diamond powder slurry to enhance diamond nucleation has been developed. Under appropriate pretreatment and growth conditions, diamond grain densities of approximately 1010 cm-2 have been obtained on fused silica substrates. The synthesis technique of ultrathin diamond film on fused silica substrates by a hot filament chemical vapor deposition was studied, and high quality ultrathin diamond films with smooth surface were obtained. The optical transmittance of the film with a thickness of approximately 0.3 micrometer on fused silica substrate reached as high as 68% at wavelength of 800 nm.