A sheet of graphene is a mere atom thick and has low resistance and high mobility making it optimal for both interconnects and semiconductor applications. (Source: University of Maryland)
New research indicates new form of carbon superior to copper for electronics
While the world of electronics has seen many changes over the years, on a hardware level it still remains very much a world of silicon and copper. Some are looking to change that. New research from the University of Maryland has, for the first time, quantitatively measured properties of electron conduction in sheets of graphene.
Graphene is an exotic form of carbon consisting of a single-atom thick layer of carbon atoms. It, along with carbon nanotubes and fullerenes, has been a hot topic in recent research, but until now scientists were unable to measure exactly how well it stacks up to copper.
Resistivity, a specific measure of resistance to electrical current, is a measure of how much electron flow is impeded and certain temperatures. An increase in temperature leads to atomic vibrations, and these wiggling atoms can collide with flowing electrons, cutting off the flow. All material experience this phenomena to some degree, except for superconductors or theoretical-only materials at absolute zero. However, good conductors experience less resistance with temperature to electron flow.
For graphene at room temperature, the true resistivity was shown to be 1.0 µohm-cm. This is approximately 35 percent less than in copper, the material with the lowest known resitivity at room temperature. Unfortunately the researchers point out that these levels are not currently reachable due to dirty graphene.
Physics professor Michael S. Fuhrer of the university's Center for
Nanophysics and Advanced Materials said, "Other extrinsic sources in today's fairly dirty graphene samples add some extra resistivity to graphene, so the overall resistivity isn't quite as low as copper's at room
temperature yet. However, graphene has far fewer electrons than copper,
so in graphene the electrical current is carried by only a few
electrons moving much faster than the electrons in copper."
Now, the goal of these researchers is to find new ways to purify graphene, so that it can eventually be used instead of copper for semiconductors.
Fuhrer closes, "We believe that this work points out the importance of these extrinsic effects, and creates a roadmap for finding better substrates for future graphene devices."
Graphene is mechanical tough, flexible, transparent, and a great conductor of heat. The new research shows that it would make an ideal double both in transistors and in interconnects, replacing silicon and copper to form ultra-high frequency circuits. Further, it could be ideally applied to vast amount of applications including photovoltaics, lcd panels, and sensors, all of which rely on optimal conductivity/electrical behavior.
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