Graphene fabrication gets a boost
R Colin Johnson
8/25/2010 8:06 PM EDT
PORTLAND, Ore. -- Graphene, which promises to solve many problems as silicon design rules approach the atomic scale, performs better when these pure carbon devices are made smaller. The catch is that at the nanoscale level, features must have atomic accuracy, including near perfect edges and monolayers.
The Energy Department's Oak Ridge National Laboratory is creating a set of tools for fabricating perfect graphene sheets, including the recent finding that electron radiation prevents connections between monolayers.
Oak Ridge researchers used supercomputers to simulate the fabrication of graphene using quantum molecular dynamics. In the process, scientists claim to have uncovered a new method of fabricating perfect edges and monolayers in graphene.
Researchers reported last year on a method called Joule heating, that uses an electric current to trim graphene edges to perfection, albeit at the expense of creating structural loops that make connections between monolayers. Using quantum molecular dynamics in their supercomputer simulations, an intermediate step in the edge-formation process was discovered. The researchers harnessed that step to perfect the fabrication method.
The group now reports that using electron irradiation during the edge formation process prevents loops between layers from forming.