Fabrication of high-quality all-graphene devices with low contact resistances

All-graphene devices are new class of graphene devices with simple layouts and low contact resistances. Here we report a clean fabrication strategy for all-graphene devices via a defect-assisted anisotropic etching. The as-fabricated graphene is free of contamination and retains the quality of pristine graphene. The contact resistance at room temperature （RT） between a bilayer graphene channel and a multilayer graphene electrode can be as low as -5 Ω.·μm, the lowest ever achieved experimentally. Our results suggest the feasibility of employing such all-graphene devices in high performance carbon-based integrated circuits.