Computer simulation to expand emission area and decrease electron beam width for cold cathode of triode‐type FEDs

Abstract

AbstractTo decrease the electron beam width and expand the emission area of a triode‐type FED using GNF, a cold cathode structure is studied by simulation. In the simulation, not only the electron beam width but also the emission current are evaluated by means of the electric field emission characteristics of a GNF cold cathode emitter. If the surface shape of the cold cathode emitter is assumed hemispherical, the electron emission from the center of the cold cathode emitter is found to increase as the center height of the emitter is increased when the separation between the gate and the cathode is 3 µm and the gate hole diameter is 10 µm. If the anode current obtained from one cold cathode is 0.1 µA for a gate‐to‐cathode separation of 3 µm, the electron beam width increases as the center height of the cold cathode emitter is increased when the gate hole diameter is 10 or 20 µm. On the other hand, the electron beam width is almost constant if the gate hold diameter is 3 or 5 µm. As the gate hole diameter is reduced, the electron beam width is reduced. If the gate hole diameter is 3 µm, the electron beam width can be made less than 100 µm regardless of the height of the center of the cold cathode emitter. Further, when the emission area is studied for a gate hole diameter of 3 µm, the emission area reaches a maximum when the center height of the cold cathode emitter is identical to the cathode electrode. © 2005 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 88(4): 28–36, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20119