Vapor deposition processes for amorphous carbon films with sp³ fractions approaching diamond

Trends in recently reported data on high sp3 fraction (up to 85%), nonhydrogenated amorphous diamond-like carbon films deposited by ion beam sputtering and laser vaporization are examined. The degree of diamondlike film character is found to depend upon the deposition technique as well as the substrate temperature and thermal diffusivity. The data suggest that the combination of incident particle kinetic energy and surface accommodation determine the physical properties of the resultant film. A model is proposed for the condensation of energetic carbon atoms into diamondlike films in which a quench-type surface accommodation mechanism is operative.