Diamonds are used to nucleate diamond and diamond-like carbon films in a chemical vapor deposition process using bias enhancement. A negative bias is applied to the substrate, such that a cationic form of the diamond is accelerated toward the substrate during the nucleation phase of the deposition. In this manner, the diamondoid may be embedded or partially embedded in the substrate and/or growing film, increasing the adhesion of the film to the substrate. According to the present embodiments, it is not necessary to mechanically pre-seed the substrate for nucleation purposes.