Direct formation of graphene-metal hybrid on dielectric surfaces by metal-induced crystallization

Large area graphene film is usually grown on a metal and then transferred to a substrate for its utilization. We report here a rapid (10 seconds) graphene growth method that can be carried out on any desired substrate, including insulator, thus negating the need for the transfer. This method is based on metal-induced crystallization of amorphous carbon to graphene, and involves a very thin metal layer that is less than 10 nm thick. Rapid thermal annealing of a bilayer of a-C and metal deposited on a given surface leads to the formation of graphene film, and subsequent breaking-up of the thin metal layer underneath the film, resulting in a graphene-metal hybrid that can be used as a transparent electrode. Post annealing, which causes agglomeration of nano-crystallites, enhances transmittance of the film without affecting sheet resistance. The nature of the growth method allows not only large area formation of graphene film but also film formation only on desired area.