Carbon nanotubes are heralded as a next-gen wonder material capable of creating everything from space elevators to better batteries, and now a team of scientists is working on creating high-performance computer chips using the microscopic fibers. The team believes that the carbon nanotubes’ electronic properties could yield performance superior to current silicon-based devices.
Reporting their discoveries in the latest Nature Nanotechnology, the team (which includes IBM materials scientist James Hannon) said that the potential for carbon nanotubes is enormous. “The problem is you have to put it in to production on a 10- or 15-year time scale, so the kinks have to be worked out in the next few years,” he said speaking to BBC News. “If you look at all the possibilities out there, there are very few that have actually produced an electronic device that would outperform silicon – there are exotic things out there but they’re all still at the ‘PowerPoint stage’.”
In their experiments, the team showed that single nanotubes demonstrated vastly superior speed and energy characteristics in the lab. The main challenges have been integration, which would involve placing billions of the tiny nanotubes on a chip with exact precision. However the team have come up with a couple of unique solutions.
The first is a chemical that coats nanotubes and makes them soluble in water. The second is a solution that binds to the first chemical and to the element hafnium, but not to silicon. The team then simply “double-dipped” the chip into the two solutions – one chemical stuck to the hafnium, and the other chemical acted as the second part of a two-part epoxy, tightly binding nanotubes to the hafnium regions on the chip but not to silicon.
Using this method, the team was able to create a series of neatly aligned nanotube devices at a density of a billion tubes per square centimeter. “That’s one nanotube every 150 or 200 (billionths of a metre) or so,” explained Dr Hannon. “That’s not good enough to make a microprocessor yet – it’s a factor of 10 away. But it’s a factor of 100 better than has been done previously.”
Via BBC News