Future electronic devices may feature extremely thin graphene nanoribbons to make them faster and more energy-efficient.
Graphene's incredible properties have made it the materials science powerhouse of the 21st century. Actually making this one-atom-thick material, however, has proven to be its biggest obstacle to adoption. Nanoribbons of graphene are a prime example of how production problems can hold back enormous potential for innovation, but now scientists report in the journal Nature Communications that they may have found a solution.
In the past, incorporating graphene nanoribbons into mass production lines for devices would have meant introducing a host of specialized equipment just for making the nanoribbons. This new method makes it possible to grow graphene nanoribbons directly on the surface of a semiconductor — in this case, the metal known as germanium.
"Graphene nanoribbons that can be grown directly on the surface of a semiconductor like germanium are more compatible with planar processing that's used in the semiconductor industry, and so there would be less of a barrier to integrating these really excellent materials into electronics in the future," said senior study author Michael Arnold of the University of Wisconsin-Madison, in a statement.
Graphene has generated a lot of buzz in recent years, and one reason is that it conducts electricity and dissipates heat way more efficiently than silicon, the standard material currently used in computer chips. The catch is that graphene doesn't perform nearly so well when electrical currents must be switched on and off — unless the graphene is in the form of nanoribbons less than 10 nanometers wide.
Creating such extremely small strips of graphene has proven to be a challenge. Other methods have succeeded in making nanoribbons that are sufficiently thin, but that have rough edges that impair their function.
This new method details the conditions necessary to get the carbon atoms from methane to stick to the surface of germanium and form graphene. The end result is nanoribbons with the smooth edges graphene needs to function properly.
The technique is still being perfected. Right now, the nanoribbons seem to grow at random spots along the surface of the germanium, so the researchers are working on imposing more order in the process.
Photo: Philippe Put | Flickr