Direct graphene synthesis on a Si/SiO₂ substrate by a simple annealing process

We report the direct synthesis of graphene on Si/SiO₂ substrates by a simple annealing process. An amorphous carbon layer and a Ni/Au layer were deposited on a Si/SiO₂ substrate, and then the sample was annealed under an H₂/Ar atmosphere. The Au layer suppressed the formation of Ni islands and graphene was synthesized at the interface between the metal and SiO₂ layers. The graphene had an effective mobility similar to that of graphene synthesized by chemical vapor deposition. The technique does not require reactive carbon source gasses and transfer processes, which makes it a practical method of graphene synthesis. (papers)