[Home]   [Full version]  

Graphene used to create world's smallest transistor

Apr 17 ,Nanotechnology



Full size image
Researchers have used the world's thinnest material to create the world's smallest transistor, one atom thick and ten atoms wide.

Reporting their peer-reviewed findings in the latest issue of the journal Science, Dr Kostya Novoselov and Professor Andre Geim from The School of Physics and Astronomy at The University of Manchester show that graphene can be carved into tiny electronic circuits with individual transistors having a size not much larger than that of a molecule.

The smaller the size of their transistors the better they perform, say the Manchester researchers.

In recent decades, manufacturers have crammed more and more components onto integrated circuits. As a result, the number of transistors and the power of these circuits have roughly doubled every two years. This has become known as Moore's Law.

But the speed of cramming is now noticeably decreasing, and further miniaturisation of electronics is to experience its most fundamental challenge in the next 10 to 20 years, according to the semiconductor industry roadmap.

At the heart of the problem is the poor stability of materials if shaped in elements smaller than 10 nanometres in size. At this spatial scale, all semiconductors -- including silicon -- oxidise, decompose and uncontrollably migrate along surfaces like water droplets on a hot plate.

Four years ago, Geim and his colleagues discovered graphene, the first known one-atom-thick material which can be viewed as a plane of atoms pulled out from graphite. Graphene has rapidly become the hottest topic in physics and materials science.

Now the Manchester team has shown that it is possible to carve out nanometre-scale transistors from a single graphene crystal. Unlike all other known materials, graphene remains highly stable and conductive even when it is cut into devices one nanometre wide.

Graphene transistors start showing advantages and good performance at sizes below 10 nanometres - the miniaturization limit at which the Silicon technology is predicted to fail.

"Previously, researchers tried to use large molecules as individual transistors to create a new kind of electronic circuits. It is like a bit of chemistry added to computer engineering", says Novoselov. "Now one can think of designer molecules acting as transistors connected into designer computer architecture on the basis of the same material (graphene), and use the same fabrication approach that is currently used by semiconductor industry".

"It is too early to promise graphene supercomputers," adds Geim. "In our work, we relied on chance when making such small transistors. Unfortunately, no existing technology allows the cutting materials with true nanometre precision. But this is exactly the same challenge that all post-silicon electronics has to face. At least we now have a material that can meet such a challenge."

"Graphene is an exciting new material with unusual properties that are promising for nanoelectronics", comments Bob Westervelt, professor at Harvard University. "The future should be very interesting".

A paper entitled "Chaotic Dirac Billiard in Graphene Quantum Dots" is published in April 17 issue of Science. It is accompanied by a Perspective article entitled "Graphene Nanoelectronics" by Westervelt.

Source: University of Manchester

Related stories:

Physicists show electrons can travel over 100 times faster in graphene than in silicon
University of Maryland physicists have shown that in graphene the intrinsic limit to the mobility, a measure of how well a material conducts electricity, is higher than any other known material at room temperature. Graphene, a single-atom-thick sheet of graphite, is a new material which combines aspects of semiconductors and metals.
IBM researchers quell nanoscale interference
IBM researchers have discovered a way to use graphite effectively in building nanoelectonic circuits vastly smaller than those in silicon-based computer chips.
Small graphene wires may be poor conductors
Ohio University physicists researching electron properties in graphene ribbons have found that narrow wires made of this material may not be good conductors.
Graphene makes movement easy for electrons
Researchers at The University of Manchester have found that electrons move more easily in graphene than all other materials, including gold, silicon, gallium arsenide and carbon nanotubes.
Move over, silicon: Advances pave way for powerful carbon-based electronics
Bypassing decades-old conventions in making computer chips, Princeton engineers developed a novel way to replace silicon with carbon on large surfaces, clearing the way for new generations of faster, more powerful cell phones, computers and other electronics.
Sheet of carbon atoms acts like a billiard table, physicists find
A game of billiards may never get smaller than this. Physicists at UC Riverside have demonstrated that graphene – a one-atom thick sheet of carbon atoms arranged in hexagonal rings – can act as an atomic-scale billiard table, with electric charges acting as billiard balls.
Graphene Nanoelectronics: Making Tomorrow’s Computers from a Pencil Trace
A key discovery at Rensselaer Polytechnic Institute could help advance the role of graphene as a possible heir to copper and silicon in nanoelectronics.
New Materials for Making 'Spintronic' Devices
An interdisciplinary group of scientists at the U.S. Department of Energy's Brookhaven National Laboratory has devised methods to make a new class of electronic devices based on a property of electrons known as "spin," rather than merely their electric charge. This approach, dubbed spintronics, could open the way to increasing dramatically the productivity of electronic devices operating at the nanoscale.

News discussion:

Nanotechnology news

[Home]   [Full version]