Morphological features of diamond films grown on diamond-like carbon films synthesized from polymer by chemical vapor deposition

Diamond crystals and films were deposited on diamond-like carbon (DLC) films which were synthesized at low pressure using polymer (phenylcarbyne [C6H5C](n)) as a precursor by hot-filament chemical vapor deposition (HFCVD) system. The morphological features of diamond crystals and films were characterized by scanning electron microscopy (SEM) and Raman spectroscopy. Various crystalline diamonds such as microcrystalline diamond grains or films, fine-grained diamond films or cluster, multiple crystals have been observed. The variation mainly depends on the structure of the DLC film as well as the deposition condition. It is proposed that during the deposition process, most of the amorphous carbon phase in the DLC film was etched away by the atomic hydrogen, while most crystalline carbon phase was still left, and diamond crystals epitaxially grow on the crystals in amorphous carbon matrix.