Growth of nanocomposite films from accelerated C sub(60) ions

A beam of accelerated C sub(60) ions is used to deposit superhard ( similar to 50GPa) carbon films that exhibit high index plasticity ( similar to 0.13-0.14) and high conductivity (up to 3000 S m super(-1)). Transmission electron microscopy, Raman spectroscopy and x-ray photoelectron spectroscopy are subsequently used to study the microstructure and bond character of the deposited films. The films consist of textured graphite nanocrystals and diamond-like amorphous carbon (DLC). The graphene plane of the nanocrystals is aligned perpendicular to the film surface. It is shown that sp super(2) bonds dominate in the films. The percentage of sp super(3) bonds depends on the ion energy and the substrate temperature, and does not exceed 40%. The obtained results suggest that a new nanocomposite material consisting of oriented graphite nanocrystals reinforced by a DLC matrix is synthesized. A simple model is proposed to correlate the excellent mechanical properties with the observed structure.