Field-Enhancement Factor of a Carbon Nanotube Cold Cathode Triode

Abstract

To estimate the field-enhancement factor, the model system of floated sphere in triode configuration of the carbon nanotube was proposed, and the actual electric field and field-enhancement factor at the apex of carbon nanotube were calculated with the image charge method analytically. The field-enhancement factor given as β=3+ρ+W, where ρ is the aspect ratio of the carbon nanotube, and W is the function of geometrical parameters and the anode and gate voltages. The geometrical parameters affects the field-enhancement factor very much, such as the field-enhancement factor decreased rapidly with the increasing of top radius of carbon nanotube, gate-cathode distance and gate-hole size. The field-enhancement factor could be improved via concocting the gate-electrode.