Graphene sheets of carbon growing on a surface of iridium grow by first forming tiny carbon domes, researchers in Italy, the UK and USA have discovered, pointing the way to possible methods for assembling components of graphene-based computer circuits, replacing silicon and metal.

The study suggests that graphene grows in the form of tiny islands built of concentric rings of carbon atoms. The islands are strongly bonded to the iridium surface at their perimeters, but are not bonded to the iridium at their centers, which causes them to bulge upward in the middle to form minuscule geodesic domes. By adjusting the conditions as the carbon is deposited on the iridium, the researchers could vary the size of the carbon domes from a few nanometers to hundreds of nanometers across.

More info: October 12 issue of Physics