Local heating method for growth of aligned carbon nanotubes at low ambient temperature

We use a highly localized resistive heating technique to grow vertically aligned multiwalled nanotube films and aligned single-walled nanotubes on substrates with an average temperature of less than 100 degrees C. The temperature at the catalyst can easily be as high as 1000 degrees C but an extremely high temperature gradient ensures that the surrounding chip is held at much lower temperatures, even as close as 1 mu m away from the local heater. We demonstrate the influence of temperature on the height of multiwalled nanotube films, illustrate the feasibility of sequential growth of single-walled nanotubes by switching between local heaters and also show that nanotubes can be grown over temperature-sensitive materials such as resist polymer. (C) 2008 American Institute of Physics. [DOI: 10.1063/1.2981398]