Carbon nanotube films prepared by thermal chemical vapor deposition at low temperature for field emission applications

Mirror-like smooth carbon nanotube (CNT) films were grown by thermal chemical vapor deposition on glass substrate at a relatively low temperature of 570°C. Cobalt-containing amorphous carbon composite films were employed as a catalyst layer for the growth of CNTs by decomposing acetylene in a tube furnace. The diameter of the CNTs was around 10 nm and the root-mean-square roughness of the film was about 12 nm, indicating a relatively smooth surface. A high emission current density of 12 mA/cm2and relatively uniform emission sites were obtained from this type of CNT films. The relatively smooth CNT films, which can be deposited at low temperature on glass substrates and compatible with current semiconductor processes, have a potential for fabricating high-density gated CNT field emitter array.