Nanotubes Outperform Copper Nanowires as Interconnects
Rensselaer Researchers have created a road map that brings academia and the semiconductor industry one step closer to realizing carbon nanotube interconnects and alleviating the current bottleneck of information flow that is limiting the potential of computer chips in everything from personal computers to portable music players.
To better understand and more precisely measure the key characteristics of both copper nanowires and carbon nanotube bundles, the researchers used advanced quantum-mechanical computer modeling 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 (CCNI), 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,” says Saroj Nayak, associate professor 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 size of computer chips has shrunk dramatically over the past decade, but has recently hit a bottleneck, Nayak says. Interconnects, the tiny copper wires that transport electricity and information around the chip and to other chips, have also shrunk. As interconnects get smaller, the copper’s resistance increases and its ability to conduct electricity degrades. This means fewer electrons are able to pass through the copper successfully, and any lingering electrons are expressed as heat. This heat can have negative effects on both a computer chip’s speed and performance.