J161032 Selectively Controlled Alignment of Single Carbon Nanotube Bundles by Dielectrophoresis

A simple and reproducible method has been developed to allign single-walled carbon nanotubes (SW-CNTs) selectively to a nano-bridge. A bundle of SW-CNTs are bridged between three-dimensional taper electrodes with a distance of a few micrometers. Dielectrophoresis (DEP) allowed us to confine CNTs along the electric field between the electrodes and a self-assembled bundle of CNTs were bridged between the electrodes. Depending on the magnitude of applied ac electric field, the shape of electrode and the duration of DEP, various shapes of bundled CNTs were obtained. The characteristics of a bundle of SW-CNTs were evaluated from Raman spectroscopy and I- V measurement. From 1-V measurement of SW-CNT bridges that were used semiconducting or metallic SW-CNT dispersion, there were distinctively different current conducting properties. This method opened a way to novel applications such as highly-sensitive and species-selective CNT gas sensors or electronic devices.