Carbon nanotube bundles have much smaller electrical resistance

Researchers at Rensselaer Polytechnic Institute have conducted research indicating that carbon nanotube interconnects can outperform copper nanowires in next-generation semi conductors.

To compare copper nanowires and carbon nanotube bundles the researchers used advanced quantum-mechanical computer modelling to run "vast simulations" on a high-powered supercomputer. It is the first such study to examine copper nanowire using quantum mechanics rather than empirical laws.

After crunching numbers for months with the help of Rensselaer’s Computational Center for Nanotechnology Innovations, the research team concluded that the carbon nanotube bundles boasted a much smaller electrical resistance than the copper nanowires. This lower resistance suggests carbon nanotube bundles would therefore be better suited for interconnect applications.

"With this study, we have provided a road map for accurately comparing the performance of copper wire and carbon nanotube wire," said Saroj Nayak, an associate professor in Rensselaer's Department of Department of Physics, Applied Physics, and Astronomy, who led the research team.

"Given the data we collected, we believe that carbon nanotubes at 45 nanometers will outperform copper nanowire."

The research results will be featured in the March issue of Journal of Physics: Condensed Matter.

Nayak said there are still "many challenges" to overcome before mass-production of carbon nanotube interconnects. There are still issues concerning the cost of efficiency of creating bulk carbon nanotubes, and growing nanotubes that are solely metallic rather than their current state being of partially metallic and partially semiconductor.

More study will also be required, he explained, to model and simulate the effects of imperfections in carbon nanotubes on the electrical resistance, contact resistance, capacitance, and other vital characteristics of a nanotube interconnect.