Computer Simulation Of Field Emission Cathode

In contrast with conventional thermo-ionic cathode, field emitter array (FEA) cathode has many special advantages, such as room-temperature operation without a cathode heater, high current density, low power dissipation, excellent ON/OFF isolation characteristics and instant turn-on characteristics. At present, FEAs have potential for use as an electron source in a wide variety of applications, including microwave power amplifiers (such as TWTs, Klystron), flat panel displays, electron microscopy, and electron beam lithography. The research focus concentrates on the use of FEAs as a cold cathode source for microwave power amplifiers or flat panel displays.Now silicon and molybdenum are the most popular materials used for tip field emitter arrays. However, both of them have disadvantages. Mo tip FEAs is fabricated by evaporating tip cathodes on base, so it has bad coherence with the base. On the other hand, the characteristics of silicon result in the bad heat stability, bad emission reliability, and low current density. It is important to seek new materials of cold cathodes, besides improve the existing technology. According to experiments, LaB6, with high conductivity, good heat stability and chemical stability, low work function, and active cathode appearance, has become an ideal material for field emission array cathodes.Simulating the electronic devices by computers, can forecast the real performance of devices before experiments. By discussing the effects of changing the size and material, we can reduce the blindness and times of experiments, and save the experiment outlay. Computer simulation of field emission cathodes is an important research topic. The aim of this paper is to discuss the effects of structure parameters on field emission performance, in order to fabricate excellent field emission cathodes. The structure of field emission triode is first simulated by MAGIC. The tip height, tip position, tip curvature, gate aperture, and gate voltage are changed, to observe the emission current and the electron congregation. In addition, the structure of field emission triode and double-gated field emission cathodes are also simulated by another software (EBS). By comparing the above results, excellent cathode structure is achieved. At last, the results about the two simulations are similar, which validate the applicability...