Properties and applications of carbon nanotubes explored. (General Developments).

Researchers at NIST are using carbon nanotubes for a variety of new experiments. Carbon nanotubes recently were discovered in the byproducts of carbon fullerene (Bucky balls) production. Nanotubes can range from a few to hundreds of nanometers in diameter and a few to tens of micrometers in length. The tubes are showing promise in a number of new areas. These include molecular electronics where the nanotubes are used as both wiring and, with modification of the nanotube itself, electronic devices. The NIST researchers are exploring the connection of nanotubes to surfaces to test the strength and electrical properties of various attachment methods. Electron beam carbon deposition (EBD) was used to attach a carbon nanotube to a tungsten force probe and to an atomic force microscope (AFM) tip. By pulling the force probe away from the AEM tip, the EBD bond survived a few micronewtons, which is a large force on a nanotube scale. Work in progress exploits the electrical properties of nanotubes for sub-micron electr ical conduction mapping using nanotubes mounted on AFM tips. The nanotubes are used as very small thin wires that can be scanned across a sample and are much more durable than commonly used metal coated AFM tips. The nanotube AFM tips also are being used to explore biological samples; since they are long and thin, they can access areas normal AFM tips cannot.

CONTACT: Paul Rice, [phone]; [e-mail].