Bias-enhanced post-treatment process for enhancing the electron field emission properties of ultrananocrystalline diamond films

The electron field emission (EFE) properties of ultrananocrystalline diamond films were markedly improved via the bias-enhanced plasma post-treatment (bep) process. The bep-process induced the formation of hybrid-granular structure of the diamond (bep-HiD) films with abundant nano-graphitic phase along the grain boundaries that increased the conductivity of the films. Moreover, the utilization of Au-interlayer can effectively suppress the formation of resistive amorphous-carbon (a-C) layer, thereby enhancing the transport of electrons crossing the diamond-to-Si interface. Therefore, bep-HiD/Au/Si films exhibit superior EFE properties with low turn-on field of E-0 = 2.6V/mu m and large EFE current density of J(e) = 3.2m/cm(2) (at 5.3 V/mu m). (C) 2015 AIP Publishing LLC.