Abstract
This letter describes the fast growth of ultrananocrystalline diamond (UNCD) films by bias-enhanced nucleation and growth process in CH 4 /Ar plasma. The UNCD grains were formed at the beginning of the film's growth without the necessity of forming the amorphous carbon interlayer, reaching a thickness of ∼380nm in 10min. Transmission electron microscopic investigations revealed that the application of bias voltage induced the formation of graphitic phase both in the interior and at the interface regions of UNCD films that formed interconnected paths, facilitating the transport of electrons and resulting in enhanced electron field emission properties. © 2014 AIP Publishing LLC.