一种平行背栅极碳纳米管阵列的场增强因子计算

建立一种平行背栅极碳纳米管阵列阴极，基于电场叠加原理，利用镜像电荷法对其进行计算，给出碳纳米管顶端表面电场增强因子。在此基础上，进一步分析器件各类参数对电场增强因子的影响。分析表明，碳纳米管阵列阴极具有最佳阵列密度，其对应碳纳米管间距大约为碳纳米管高度的两倍，靠阴极阵列边缘部位的碳纳米管发射电子能力比其中心部位的大。除了碳纳米管的长径比之外，栅极宽度、栅极厚度和栅极间距等也对电场增强因子有一定的影响:栅极越宽，场增强因子越大;而栅极厚度、栅极间距越大，场增强因子就越小。

Modeling Calculation for Field Enhancement Factor on A Carbon Nanotube Array with Parallel Back-grid

A model on the carbon nanotube array with parallel back-grid was proposed. The actual electric field at the top of carbon nanotubes and field enhancement factor were calculated analytically by using mirror image charge method based on the superposition principle of electric field. The effects of the geometrical parameters of the carbon nanotube device on the field enhancement factor were investigated. The calculation results show that the carbon nanotube array has the best density for field emission, the inter-tube distances are double height of carbon nanotubes and the electron emission ability of carbon nanotube near the edge of carbon nanotube array is larger than the carbon nanotube at the center of this array. The field enhancement factor increases with the width of back-grid, and decreases with the thickness and space of the back-grids.