排列形状及阵列数目对纳米导线阵列场发射性能的影响

为了进一步研究纳米导线阵列的排列形状以及阵列数目对其场发射行为的影响，利用镜像悬浮球模型对正方形以及六边形排列的纳米导线阵列的场发射行为进行计算与模拟，近似的得到纳米导线阵列的场发射增强因子满足如下的变化趋势：β=h/ρ(1/1+W)+1/2(1/1+W)²+3,其中h为纳米导线的高度，ρ为纳米导线的半径，W是以R为自变量的函数，R为纳米导线阵列的间距.结果显示纳米导线阵列的排列形状对其场发射性能的影响较小，而阵列间距则是影响场发射性能的关键因素：当R<R₀时，场发射增强因子随着阵列间距的减小而急剧减小；当R>R₀时，场发射增强因子基本不变，其中R₀为导线阵列场发射的最佳间距.进一步研究表明改变纳米导线阵列的数目基本不会改变阵列的场发射性能随间距的变化趋势，但是随着阵列数目的增加，R₀会有一定程度的减小，场发射增强因子也会降低. 关键词： 纳米导线 场发射 增强因子 阵列数目

Influence of arrangement and matrix number on the field emission from conductive nanowire array

In order to further study the influence of the arrangement and matrix number of the conductive nanowires array on the field emission from the array, the more practical conductive hexagonal and square nanowire arrays were simulated with the mirror image floating sphere model in this paper. From the calculation results, the field enhancement factor of conductive nanowire array was expressed as the following expression:β=h/ρ(1/1+W)+1/2(1/1+W)²+3, in which h is the height of conductive nanowire, ρ is the radius and W is a function of the independent variable R, R is the interwire distance. All calculated results indicated that the arrangement of conductive nanowires array has less influence on the field emission, while the interwire distance critically affects the field emission. As R<R₀, the field enhancement factor decreases rapidly with R. When R>R₀, the enhancement factor hardly changes, where R₀ is the optimized interwire distance. The performance of field emission from conductive nanowire array hardly changes with the matrix number of the array, which only influences on the gradient curve of the enhancement factor. R₀ would decrease to some extent with the increasing of the matrix number.