Field Emission Characteristics of the Structure of Vertically Aligned Carbon Nanotube Bundles

In this study, we performed thermal chemical vapor deposition for growing vertically aligned carbon nanotube (VACNT) bundles for a field emitter and applied photolithography for defining the arrangement pattern to simultaneously compare square and hexagonal arrangements by using two ratios of the interbundle distance to the bundle height (R) of field emitters. The hexagon arrangement with R = 2 had the lowest turn-on electric field (E(to)) and highest enhancement factor, whereas the square arrangement with R = 3 had the most stable field emission (FE) characteristic. The number density can reveal the correlation to the lowest E(to) and highest enhancement factor more effectively than can the R or L. The fluorescent images of the synthesized VACNT bundles manifested the uniformity of FE currents. The results of our study indicate the feasibility of applying the VACNT field emitter arrangement to achieve optimal FE performance.