Controllable gallium melt-assisted interfacial graphene growth on silicon carbide

Liquid gallium on the silicon carbide (SiC) surface forms graphene directly on non-conductive SiC surfaces at lower temperatures than are required for SiC decomposition. The uniformity and reproducibility across large areas have been one challenge. In this paper we demonstrate controllable growth of graphene with uniform characterization across the film surface. We show that material from the reaction cell was incorporated into the graphene films, which would likely work for many different materials and dopants. But when no other component is added, controllable graphene films will form with reproducible characterization over the entire surface contacted by the gallium flux. Additional carbon dissolved in the gallium can be used to cause a uniform layer of graphite crystals form and adsorb on the outer layer of the graphene films. These different pathways for gallium melt-assisted interfacial graphene (MAIG) growth can be used to tailor the production of graphene.

► Molten gallium can promote uniform epitaxial growth of graphene if it only touches silicon carbide and inert materials.
► Material, including SiO2, from a solid support can be incorporated into graphene being formed by Ga-MAIG.
► Excess carbon produces sub-micron graphite crystals that deposit on the graphene surface and increase the surface area.
► Uniform growth, doping from a solid support, and adding excess carbon could be used to produce patterned graphene.