Observation of Band Gap in Epitaxial Bilayer Graphene Field Effect Transistors

Bilayer graphene was grown on the Si-face of SiC by thermal decomposition. Its electronic properties were investigated in top-gate Hall bar devices. By controlling the carrier density using gate voltage, we were able to access the charge neutrality point. The conductance at the charge neutrality point showed a strong temperature dependence, and its temperature dependence was well fitted with thermal activation and variable-range hopping mechanisms. The electrical detection of a band gap opening in bilayer graphene grown on SiC is a promising step toward the realization of graphene-based electronics using epitaxial graphene. (C) 2011 The Japan Society of Applied Physics