FABRICATION OF THIN-FILM COLD CATHODES BY A MODIFIED CHEMICAL-VAPOR-DEPOSITION DIAMOND PROCESS

Thin-film cold cathodes have been grown on molybdenum by a modified mi crowave assisted plasma chemical vapor deposition diamond process. Ele ctron field-emission tests have been performed on the devices. The mod ification from the chemical vapor deposition diamond process includes the addition of N-2 and O-2 into the plasma during the growth stage. C haracterization of these films indicates a disordered tetrahedral carb on structure. Raman spectroscopy shows a disturbance in the cubic symm etry of the lattice and x-ray diffraction indicates a disordered tetra hedral structure. Electron emission testing indicate low turn-on volta ges. Current densities from 1 to 8 mA/cm(2) can be obtained for applie d fields of 5-8 V/mu m. The results are explained in terms of a change in the electronic band structure and the formation of states in the b and gap. (C) 1998 American Vacuum Society. [S0734-211X(98)09502-X].