Carbon SWNTs as wires and structural templates between nanoelectrodes

The adsorption of carbon SWNTs from purified aqueous dispersions on electrode patterns is described. As an alternative approach to electrically contacted SWNTs, mixed Langmuir films consisting of surfactant molecules and SWNTs were transferred onto electrode arrays. Room temperature conductivity measurements on both types of samples revealed a (two point) resistance in the MΩ range. From these values, the presence of a closed surfactant layer between the tubes and electrode surface is excluded. As a step towards increasing the functionality of SWNTs, gold particles were attached to SWNT ropes after chemical tube modification by a two-step oxidation process. Using this technique, lateral electrode lines (100 nm distance) can be connected by a chain of closely arranged nanoparticles.