Novel surface chemical synthesis route for large area graphene-on-insulator films

Abstract

The feasibility of a halogen-based surface chemical route to the synthesis of large area graphene-on-insulator films is reported. Both CF4- and Cl2-based plasmas have been used to etch 6H-SiC (0001) surfaces, which were then annealed at 970 °C. These surfaces were characterized using x-ray photoelectron spectroscopy, reflection high energy electron diffraction, atomic force microscopy, and Raman spectroscopy. It was shown that the etching process leads to selective removal of silicon from the SiC matrix to produce carbon rich surface layers. When annealed, these layers reconstruct to form a graphene film. Electrical measurements indicated the resistivity and carrier density of these films are similar to those of few layer graphene.