Vectorial growth of metallic and semiconducting single-wall carbon nanotubes

A new approach for vectorial growth of single-wall carbon nanotube arrays is presented. The origin of growth is defined by patterning the catalyst nanoparticles, while the direction of growth is defined by a local electric field parallel to the substrate. Statistical analysis of the nanotube angular distribution indicates that field-directed growth can discriminate between metallic and semiconducting nanotubes during their formation. Vectorial growth could be used to produce nanotube-based circuitry for molecular electronics.