Field-emission characteristics of nitrogen-doped diamond-like carbon film deposited by filtered cathodic vacuum arc technique

We have fabricated silicon field-emitter arrays coated with nitrogen-doped diamond-like carbon (DLC) films which were deposited by a filtered cathodic vacuum arc technique. The DLC coating on silicon emitters improved the emission characteristics including turn-on electric field and emission current. The turn-on electric fields of DLC-coated silicon emitters are 6.8, 4.0, 1.9, and 0.8 V/μm when the nitrogen flow rates are at 0, 5, 7, and 10 sccm, respectively. The turn-on electric field of the non-coated silicon emitter is 16.0 V/μm. The work functions of DLC-coated silicon emitters have been estimated from Fowler-Nordheim plots and were reduced from 1.86 eV in undoped DLC films to 0.47 eV in 10 sccm of nitrogen doped DLC-coated emitter. As the nitrogen doping concentration of the DLC-coated silicon emitters is increased, the field emission properties improved.