On the enhancement of field emission performance of ultrananocrystalline diamond coated nanoemitters

Ultrananocrystalline diamond (UNCD) nanoemitters were synthesized by a microwave plasma enhanced chemical vapor deposition process using silicon nanowires (SiNWs) as the template. Preseeding markedly enhances the nucleation of diamond on the SiNW templates, resulting in UNCD grains of smaller size and uniform distribution, which leads to significantly improved electron field emission (EFE) properties. The EFE for UNCD nanoemitters can be turned on at (E(0))(UNCD-NE)=4.4 V/mu m, achieving large EFE current density, (J(e))(UNCD-NE)=13.9 mA/cm(2) at an applied field of 12 V/mu m, which is comparable with that of carbon nanotubes, but with much better processing reliability. (c) 2007 American Institute of Physics.