Patterning technology of carbon nanotubes for field emission displays

Abstract
Patterning technology of fine carbon nanotube (CNT) pixels on a hard metal has been developed by using photolithography process for field emission displays (FEDs). The photolithography method produced much sharper and smaller CNT pixels compared with those made by the conventional screen-printing process. The CNTs in the patterned pixels by photolithography were uniformly distributed in a 2 in. diagonal area. The density of CNT bundles in the patterned pixels was about 10/μm2. After patterning and heat treatment process below 300 °C, most of CNT bundles on the cathode were aligned perpendicular to the substrate. The turn-on field of patterned CNTs was less than 4.2 V/μm and the current density was about 2.1 mA/cm2 at 6 V/μm. This process might be applicable to field emitter arrays for high resolution FEDs.