Graphene Provides Foundation For New Electronics
Washington DC (SPX) Apr 17, 2006
A study of how electrons behave in circuitry made from ultrathin layers of graphite – known as graphene – suggests the material could provide the foundation for a new generation of nanometer scale devices that manipulate electrons as waves – much like photonic systems control light waves.
In a paper published April 13 in Science Express, an online advance publication of the journal Science, researchers at the Georgia Institute of Technology and the Centre National de la Recherche Scientifique (CNRS) in France report measuring electron transport properties in graphene that are comparable those seen in carbon nanotubes.
Unlike carbon nanotubes, however, graphene circuitry can be produced using established microelectronics techniques, allowing researchers to envision a "road map" for future high-volume production.
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The key to properties of the new circuitry is the width of the ribbons, which confine the electrons in a quantum effect similar to that seen in carbon nanotubes. The width of the ribbon controls the material's band-gap. Other structures, such as sensing molecules, could be attached to the edges of the ribbons, which are normally passivated by hydrogen atoms.
Beyond coherence and high electron mobility, the researchers note that the speed of electrons through the graphene is independent of energy – just like light waves. The electrons also possess the properties of Dirac particles, which allow them to travel significant distances without scattering.
Among the challenges ahead is improving the techniques for patterning the graphene, since electron transport is affected by the smoothness of edges in the circuitry. Researchers will also have to understand the material's fundamental properties, which could still contain "show-stoppers" that might make the material impractical.
De Heer has seen hints that graphene may offer some surprises. "We already have indications of some new and surprising electronic properties of this material," he said. "It is doing things that we have never seen in two-dimensional materials before."
Washington DC (SPX) Apr 17, 2006
A study of how electrons behave in circuitry made from ultrathin layers of graphite – known as graphene – suggests the material could provide the foundation for a new generation of nanometer scale devices that manipulate electrons as waves – much like photonic systems control light waves.
In a paper published April 13 in Science Express, an online advance publication of the journal Science, researchers at the Georgia Institute of Technology and the Centre National de la Recherche Scientifique (CNRS) in France report measuring electron transport properties in graphene that are comparable those seen in carbon nanotubes.
Unlike carbon nanotubes, however, graphene circuitry can be produced using established microelectronics techniques, allowing researchers to envision a "road map" for future high-volume production.
>
>
The key to properties of the new circuitry is the width of the ribbons, which confine the electrons in a quantum effect similar to that seen in carbon nanotubes. The width of the ribbon controls the material's band-gap. Other structures, such as sensing molecules, could be attached to the edges of the ribbons, which are normally passivated by hydrogen atoms.
Beyond coherence and high electron mobility, the researchers note that the speed of electrons through the graphene is independent of energy – just like light waves. The electrons also possess the properties of Dirac particles, which allow them to travel significant distances without scattering.
Among the challenges ahead is improving the techniques for patterning the graphene, since electron transport is affected by the smoothness of edges in the circuitry. Researchers will also have to understand the material's fundamental properties, which could still contain "show-stoppers" that might make the material impractical.
De Heer has seen hints that graphene may offer some surprises. "We already have indications of some new and surprising electronic properties of this material," he said. "It is doing things that we have never seen in two-dimensional materials before."