Improvement of electron field emission properties of nanocrystalline diamond films by a plasma post-treatment process for cathode application in microplasma devices

摘要: The electron field emission (EFE) properties of nanocrystalline diamond (NCD) films were markedly enhanced when prepared with a plasma post-treatment on the ultra-small-grain granular-structured films, as compared conventional NCD directly grown Si using CH4/Ar/H2 plasma. Transmission microscopy reveals that primary influence for improvement EFE these was owing to an induction nanographitic phase in while ultrasmall grains (∼5 nm) coalesced form large (∼hundreds nanometers) during process. This modification granular structure greatly negative bias voltage (−300 V) applied Moreover, three-electrode microplasma devices performed overwhelmingly better than two‐electrode devices, exhibiting higher current density longer lifetime stability. These devices...