前栅极冷阴极器件中单根纳米线表面电场分布研究

Electric Field Distribution of Individual Nanowire in Normal-gated Field Emission Device

利用静电场理论,对带栅极纳米线场发射冷阴极器件模型进行电场计算,在此基础上,进一步对器件几何参数以及电压对纳米线顶端表面电场的影响做了理论分析。结果表明,在纳米线低于栅极的情况下,纳米线顶端表面电场强度比其他点更强,随着离纳米线顶端距离的增加,电场急剧下降;栅孔半径、阴极与栅极距离的减小以及纳米线长度的增加,均使纳米线顶端表面电场大大增强,而栅极与阳极间距变化对顶端表面电场的作用很微弱;另外,纳米线顶端表面电场随栅极和阳极电压的增加而大幅度增强,尤其栅极电压的变化对纳米线顶端表面电场的影响更大。

The influences of some parameters of a gate field emission nanowire cold cathode device on the electric field of nanowire top are studied in this paper. The spatial distribution of the electric potential and field near the top of an individual nanotwire during the field emission were analytically calculated on the basis of classical electrostatic theory. The calculated results showed that the electric field intensity is very strong near the nanowire top, and drops abruptly with the increasing of the distance from the nanowire top. The electric field intensity of the nanowire top surface decreases with the increments of the gate hole radius and the cathode-gate electrode distance, and increases with the increasing of the nanowire length. The effect of gate-anode distance on the electric field around the top surface of the nanowire is very weak, when the gate-anode spacing is comparatively large. Moreover, the electric field of the nanowire top surface increases with the increment of anode voltage and gate voltage; especially, the effect of gate voltage on the electric field of nanowire top surface is stronger.