Fabrication of carbon nanotube field emission cathodes in patterns by a laser transfermethod

Abstract

This study reports a novel approach, based on the method of laser inducedpattern transfer, that can deposit patterned carbon nanotube (CNT) fieldemission cathodes on a variety of substrates at room temperature and in anambient environment. Tests of emission characteristics of the fabricatedcathodes present favourable emission current flux, low threshold electrical field,1 mA cm−2 currentdensity at 3.3 V µm−1 for the 8 µm thick film and good emission focusing. Well-defined CNT patterns with a feature size down to10 µm were produced using a mask. Compared with CNT film produced by printing basedmethods, higher density and better adhesion were achieved, without any post-treatment.Control of the film thickness can plainly be accomplished by adjusting the coated CNT filmthickness on the support and the number of laser pulses. The fast deposition rate and highdegree of feasibility of using the substrate, as well as the fabrication environment, renderthe proposed approach a potential method for low cost fabrication of precision patterns forCNT.