Patterning flexible single-walled carbon nanotube thin films by an ozone gas exposure method

Patterning is an essential and important process for the future use of single-walled carbon nanotube (SWCNT) thin films (TFs) in electronic devices. Different from traditional Si based electronic materials, SWCNTs can be easily etched when exposed to an oxidative atmosphere. Here we propose a gas exposure method to pattern SWCNT TFs on flexible polymeric substrates, without using vacuum and high temperature treatment. By simply exposing them to ozone for 3 mm, a high quality SWCNT TF (35-40 nm in thickness) pattern is obtained on a poly (ethylene terephthalate) substrate. It is found that the ozone can chemisorb on, functionalize and etch SWCNTs and then destroy the electrically conductive network of SWCNT TFs, which causes a fast resistance increase and achieves efficient SWCNT TF patterns. The proposed patterning method has the advantages of high efficiency, low cost and scale-up ability, and more importantly, it is suitable for assembling flexible electronic devices, indicating prospects for the low-cost and large-scale manufacture of such items. (C) 2012 Published by Elsevier Ltd.