薄膜场发射阴极中纳米线密度的理论优化

现在人们正在研究各种纳米线薄膜 ,因为它们很有可能成为新一代的场发射阴极而被应用于平面显示器等器件中。研究表明 ,除了纳米线的物理特性 ,薄膜的场发射特性也强烈地依赖于纳米线阵列的几何构造。一方面 ,薄膜阴极的纳米线阵列密度要足够大 ,使得大量的场发射源能够产生。另一方面 ,过大的密度带来的屏蔽效应将严重削弱纳米线尖端的局域电场。在本文的参数下 ,利用Ansys软件计算出了纳米线的最佳间距———使得纳米线之间的屏蔽效应可以忽略的最小距离———为纳米线高度的两倍

Theoretical Optimization of Nanowire Density of Thin Film Field Emission Cathodes

A variety of nanowire thin films are being studied as candidates for the next generation of field emission cathodes to be used in devices like planar displays.Besides the physical properties of the involved nanowires,the field emission performance of these thin films depends remarkably on the geometric configuration of the nanowire array.On the one hand,the nanowire density of an array in a thin film cathode has to be large enough to ensure a large number of field emission sources.On the other hand,screening effect sharply lowers the local electric field at the nanowire tips when the density is too high.We use Ansys to optimize the inter nanowire distance,compromising the density of field emission sources and the screening effect.We conclude that at the specific parameters the screening effect is negligible when the inter nanowire distance is larger than twice the nanowire height.