A mechanism of field electron emission from nanoclustered carbon materials

The chemical vapor deposition (CVD) method was used to grow carbon films wi th different crystalline structures that vary from polycrystalline diamond to nanoclustered graphite. A comparative study of their phase composition, structure, and field electron emission (FEE) properties has shown that the best emissivity takes place for nanoclustered graphite films and is charact erized by a threshold electric field of less than 1.5 V/mu m, an emission c urrent density of up to 10 mA/cm(2), and an emission site density of more t han 10(6) cm(-2). These graphite nanoclustered films showed cathodoluminesc ence (CL) bands at photon energies of 2.6 and 3.6 eV. The features of CL an d the enhanced FEE are explained by the modification of electron configurat ion of carbon atoms at the edge of graphite planes in the nanoclusters orie nted preferably along the substrate surface normal.