Intel wants to replace copper wires with carbon nanotubes

Future processors and other chips from Intel may feature carbon nanotubes instead of copper wires. Currently the chip giant is testing whether the theories about the properties of carbon nanotubes are accurate. They've already created some carbon nanotube interconnect prototypes and are testing the performance.

Mike Mayberry, director of components research at Intel's labs in Oregon, will discuss the research at the International Symposium for the American Vacuum Society next week in San Francisco. Intel worked with California Institute of Technology, Columbia University, University of Illinois at Urbana-Champaign, and Portland State University on the project.

Chip interconnects have become a looming headache for chipmakers. Under Moore's Law, chipmakers shrink the components inside semiconductors every two years. Shrinking interconnects, however, increases electrical resistance, which in turn reduces performance. Chipmakers switched from aluminum to copper interconnects in the late 1990s to get around the problem. Unfortunately for Intel and other companies, the resistance will start to become a significant problem in smaller copper interconnects in the coming years.

Some of the advantages of carbon nanotubes:

• They conduct electricity a lot better than metals. Electrons can flow through this material without any collisions (ballistic conduction).
• Nanotubes can be made much thinner than metal interconnects can be made. This is slowly becoming a problem for copper interconnects.

However, there's also a major disadvantage. Currently carbon nanotubes are still difficult to mass produce, researchers still need to figure out ways to produce uniform carbon nanotubes, or quickly separate the good ones from the chaff.