Turbostratic multilayer graphene synthesis on CVD graphene template toward improving electrical performance

Multilayer graphene was synthesized by overlayer growth of graphene on a monolayer graphene template using a chemical vapor deposition method under a high process temperature of 1300 °C. Structural analysis using Raman spectra revealed that the synthesized multilayer graphene forms highly crystalline graphene layers with a turbostratic stacking structure. Atomic force microscope images indicated that the step edges of the grown graphene layer proceed via lateral growth mode. The electrical transport properties of the synthesized multilayer graphene showed higher conductivity and carrier mobility than those of the monolayer graphene template. The improvement of the electrical transport properties is caused by the turbostratic stacking structure that has the electronic band dispersion similar to that of monolayer graphene. This result means that the synthesis of graphene layers grown on the graphene template is effective to improve the carrier transport properties in multilayer graphene sheets.