大电流稳定发射铁电阴极的模拟与实验研究

Simulation and Experimental Investigations of an Efficient and Stable Ferroelectric Cathode

讨论了铁电阴极的发射机理,借助MAFIA对不同电极结构的铁电阴极表面电场分布进行了模拟 计算．计算中发现,发射面电极结构对铁电阴极表面三界点处的场增强效应影响很大,特别是具有孤岛 电极结构的铁电阴极具有更大的三界点场强,从而获得更大和更稳定的发射电流．通过对电极结构及 其工艺的改进,使用PLZT铁电阴极在实验中得到了大于100A的电流．

The mechanism of electron emission from ferroelectric cathode is introduced. Distribution of the applied static field in ferroelectric cathodes is simulated by MAFIA codes. It is shown that the structure of front electrode can obviously influence the static field at the triple-point of ferroelectric cathode. A ferroelectric cathode with isolated electrodes can attain stronger multiplicative field at the triple-point, which may be helpful in getting efficient and stable electron emission. In the recent experiments, we have already got stable electron emission over 100A from a PLZTS/65/35 cathode with isolated electrodes.