IBM researchers build carbon molecule computer

(www.pcpro.co.uk)

A group of US researchers at IBM's Thomas J. Watson Research Center claim to have built the first computer circuit on a molecule.

Using 12 field effect transistors stretched along a single carbon molecule in the form of a nanotube, the scientists managed to run the logic circuit at some 52MHz.

That will hardly set the world alight with today's Gigahertz PCs. However, the researchers were not interested in building processors at this point, rather they wanted to test the switching speed of their design.

They were impressed with the results. The 52MHz achieved is some 100,000 faster than any previous recorded speeds for carbon nanotube circuits.

Making advances in nanotube technology is seen as the pathway to keeping up with Moore's Law: that the complexity of computer processors will double every 18 months.

Chip makers such as Intel and AMD have taken the manufacture of circuits down to 90nm and smaller in the bid to up the transistor density and complexity of chips in tune with this 'law', but they will at some point reach the limits of the material they are working with: silicon.

When working at such a small scale, electrons can jump from one track or path to another, and resistance is increased.

The researchers said that nanotube circuits offer negligible resistance, and current can flow extremely quickly, while the likelihood of electrons jumping from 'tube' to 'tube' is very low.