APPLICATIONS OF TECHNOLOGY:
|Researcher, Alex Zettl, shown here with a model of a carbon nanotube, has made ball bearings and mechanical switches far too small to be seen without the aid of an electron microscope.
- Electronic devices (Schottky barriers, PN junctions,
- Computation elements
- High-strength fibers
- Electronically, mechanically or thermally controlled
- Ingredients in "smart materials" (e.g.
crack self-sensing materials)
- Can be used to form electronic, thermal, electromechanical or thermomechanical devices on the scale of 1-2 nanometers
- High temperature stability (good resistance to interdiffusion)
- High potential device density
- High thermal conductivity
- High mechanical strength
Alex Zettl, Vincent Crespi, Marvin Cohen and Steven Louie at Berkeley Lab have designed carbon nanotube
structures that enable the creation of nanometer-scale
diodes, transistors and sensors. These carbon nanotubes,
containing metal/semiconductor or semiconductor/semiconductor
junctions, may be used to form electronic devices which
are 1-2 nanometers in each dimension. Nanoscale devices
envisioned include Schottky barriers, quantum wells
and transistors 10,000 times smaller in area than present
commercial silicon devices.
A novel topological solution that matches tubes with
different electronic structures enables the creation
of these junctions. Carbon nanotubes are synthesized
to contain pentagon-heptagon pair defects in their normal
hexagonal structure. The defects change the helicity
of the nanotube and alter its electronic structure.
In addition to forming all carbon heterojunctions, the
tubes can be doped with boron or nitrogen to add charge
carriers to the semiconducting region.
STATUS: U.S. Patent #6,538,262 and U.S. Patent #6,835,952. Available for licensing.
REFERENCE NUMBER: IB-1181
FOR MORE INFORMATION PLEASE SEE:
L., Crespi V., Benedict L.H., Louie S.G., Cohen M.L., "Pure
Carbon Nanoscale Devices", Physical Review Letters,
1996, 76, 6, 971.
THESE OTHER BERKELEY LAB TECHNOLOGIES IN THIS FIELD: