Scientists reveal first functional graphene semiconductor
After many years of speculation, it appears that researchers have successfully developed a chip based on the 'wonder material' graphene.
In a newpaper published in Nature, a team from Georgia Institute of Technology demonstrated a functional graphene semiconductor which is suitable for use in nanoelectronics.
Graphene is a material made from a single sheet of carbon atoms — a 2D material held together by extremely strong chemical bonds. Its composition makes it 200 times stronger than steel, yet also incredibly flexible. Graphene's diverse properties also make it ideal for use in electrical devices and batteries, since it can be printed on glass, plastics or fabrics.
But its potential as a semiconductor holds the most promise. Silicon is reaching its physical limit, and requires more and more energy to precisely control the movement of electric current. Graphene requires less energy, which reduces the need to dissipate excess heat.
So why has it taken so long for this breakthrough? The main hurdle is the 'band gap problem' – a property that allows semiconductors to switch on and off. Graphene doesn't have a band gap. However, the Georgia team figured out how to grow graphene on special silicon carbide chips. This process resulted in epitaxial graphene – a single layer of graphene grown on a crystal face. The researchers found that, when bound to the silicon carbide surface, epitaxial graphene could show semiconducting properties.
"We don't know where this will end but we know we're opening the door for a major paradigm shift in electronics," said lead author Walter de Heer of the Georgia Institute of Technology in the US in a press release. "Graphene is the next step. Who knows what the next steps are after that, but there's a good chance graphene could take over be the paradigm for the next fifty years."
