Aligned single-walled carbon nanotube patterns with nanoscale width, micron-scale length and controllable pitch

We have successfully aligned single-walled carbon nanotubes (SWNTs) in patterns with nanoscale width, micron-scale length and controllable pitch on SiO₂/Si substrates using a poly(dimethysiloxane) (PDMS) microchannel mold. The microchanneled mold was patterned with a funnel-shaped channel to minimize nanotube jamming during capillary-driven inflow. Two (i.e. pre- and post-capillary) gas blows were employed to improve nanotube alignment. The fluidically pre-aligned carbon nanotubes were 'gas-spun' into a long 20 nm wide pattern, significantly narrower than the fluidic pre-alignment channel. These narrow and long aligned SWNT patterns were successfully transferred to a pair of gold electrodes spaced 15 μm apart. The performance of the carbon nanotube field effect transistor (CNTFET) fabricated by this technique was evaluated.