Abstract
Carbon nanotubes (CNTs) and fibers (CNFs) with different microstructures were adopted for field emitters which were fabricated through screen printing methods. Carbon materials with different morphologies such as entangled, straightand bundle structures were obtained from the floating catalyst method under different growth conditions and carbon sources. CNT paste for screen printing was prepared by mixing the carbon materials with solvent and silver paste. The paste was then screen printed onto the Ag electrode which was pre-patterned on an alumina substrate. After sintering in H2+Ar atmosphere, the field emission properties of the electrode were measured. The results revealed that the emission performance of the carbon materials is bundle CNTs > straight CNTs > entangled CNTs > CNFs, which is corresponding to the crystallization of graphite layer of the tested carbon materials. The microstructures of CNTs and CNFs were studied using FE-SEM, TEM, and Raman spectroscopy, and the edge effect of cathode was investigated with different cathode configurations. In this work, a simple method to achieve lower turn-on and threshold voltages was demonstrated