Comparison of field-electron emission from different carbon nanotube array structures

Abstract

The effect of macroscopic cathode structures, which consisted of an array of the identical vertically aligned carbon nanotube (VACNT) columns in a particular arrangement, on the field emission was investigated. The electric field simulation based on the FEMLAB code showed characteristics of edge-induced U-shaped field distribution on CNT column. It was found that the degree of the field screening was dependent on VACNT-column array patterns, and that the overall field distribution depended on a number of VACNT columns at the periphery for the finite array size. Three different types of VACNT-column array cathodes were fabricated and tested for the field-electron emission: square, hexagonal, and triangular pattern arrays. All these VACNT-column array cathodes showed excellent electron-emission characteristics and a general trend consistent with field distribution simulations.