The unique electrical properties of carbon nanotubes have made them ideal candidates for their use in future molecular electronics. The successful application and mass production of CNT-based nanoelectronics will require methods for the efficient and reliable fabrication of large numbers of CNT devices simultaneously across a substrate. Here we present recent experiments on the generation of electrically conductive carbon nanotube bridged structures fabricated in parallel by magnetic entrapment. By utilizing devices composed of individually addressed nickel lines and containing gaps 1 micron wide, we have demonstrated that moderate external magnetic fields can induce domain alignment in the ferromagnetic material and generate locally intense fields within the feature junctions able to attract and bind carbon nanotubes. Magnetic field strength, nanotube solution concentration, and feature gap width and thickness are used to control the trapping process. Junctions ranging from 2-4 microns were selective for large tube bundles while devices containing gaps of 1 micron or less were more selective for individual CNTs or small ropes of tubes. By making use of electrically isolated devices on silicon containing a thermally grown oxide layer we have measured the basic electrical properties of the bridged structures.
D. P. Long
Center for Bio/Molecular Science and Engineering
Naval Research Laboratory
4555 Overlook Ave. S.W.
Washington, DC 20375 USA
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