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View Full Version : After silicon: graphine



Dr Mordrid
1st March 2007, 01:08
Graphine is a 1-atom thick sheet of graphite.

Story.... (http://www.physorg.com/news91891899.html)

New graphene transistor promises life after death of silicon chip

Researchers have used the world's thinnest material to create the world's smallest transistor – a breakthrough that could spark the development of a new type of super-fast computer chip.
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Professor Geim and colleagues have shown for the first time that graphene remains highly stable and conductive even when it is cut into strips of only a few nanometres wide.

All other known materials – including silicon – oxidise, decompose and become unstable at sizes tens times larger.

This poor stability of these materials has been the fundamental barrier to their use in future electronic devices – and this has threatened to limit the future development of microelectronics.

"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," says Professor Geim.

The research team suggests that future electronic circuits can be carved out of a single graphene sheet. Such circuits would include the central element or 'quantum dot', semitransparent barriers to control movements of individual electrons, interconnects and logic gates – all made entirely of graphene.

Geim's team have proved this idea by making a number of single-electron-transistor devices that work under ambient conditions and show a high-quality transistor action.

"At the present time no technology can cut individual elements with nanometre precision. We have to rely on chance by narrowing our ribbons to a few nanometres in width," says Dr Leonid Ponomarenko, who is leading this research at The University of Manchester. "Some of them were too wide and did not work properly whereas others were over-cut and broken."

But Dr Ponomarenko is optimistic that this proof-of-concept technique can be scaled up.

"To make transistors at the true-nanometre scale is exactly the same challenge that modern silicon-based technology is facing now. The technology has managed to progress steadily from millimetre-sized transistors to current microprocessors with individual elements down to tens nanometres in size.
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Professor Geim does not expect that graphene-based circuits will come of age before 2025. Until then, silicon technology should remain dominant.

But he believes graphene is probably the only viable approach after the silicon era comes to an end.

"This material combines many enticing features from other technologies that have been considered as alternatives to the silicon-based technology.

"Graphene combines most exciting features from carbon-nanotube, single-electron and molecular electronics, all in one."