Atom-thick graphene transistor could solve problem of silicon chips

Scientists in England say they have created the world's smallest transistor — one atom thick — that could lead to a new type of computer chip faster and smaller than today's silicon-based technology.

The researchers at the University of Manchester said in a report published in the March issue of thejournal Nature Materials that they made the chip out of the world's thinnest material, graphene.

Graphene is a flat sheet of carbon that is extremely stable, strong and flexible, and has high electrical conductivity with little resistance. Electrons — negatively charged subatomic particles — travel along the sheet in a manner that mimics the speed of light.

Graphene was discovered in 2004 by the University of Manchester team, which made a cruder version of the transistor at the time.

The new, more stable transistor could be the answer to a looming problem that faces computer chip makers: how to continue to improve technology at a rate that matches Moore's Law.

Moore's Law, in its most popular formulation, describes the advancing ability of manufacturers to squeeze more components such as transistors onto a circuit — and therefore more computing power — at a rate that doubles about every two years.

But the physical limits of Moore's Law are being approached as miniaturization reaches the molecular scale.

The new transistor created by Prof. Andre Geim's team is just a few billionths of a metre — or nanometers — across and could solve that problem.

"We have made ribbons only a few nanometres wide and cannot rule out the possibility of confining graphene even further — down to maybe a single ring of carbon atoms," Geim said in a written statement.

He said entire circuits could eventually be cut from a single sheet of graphene, but does not believe the technology will be broadly available commercially before 2025.

Last fall, Geim was awarded the 2007 Mott Medal and Prize by England's Institute of Physics for leading the researchers whose discovery of graphene led to a new category of material known as two-dimensional atomic crystals.