Graphene grown on metal surface, Cu(111), with a boron nitride(BN) buffer layer is studied for the first time. Our first-principles calculations reveal that charge is transferred from the copper substrate to graphene through the BN buffer layer which results in a n-doped graphene in the absence of a gate voltage. More importantly, a gap of 0.2 eV which is comparable to that of a typical narrow gap semicondutor opens just 0.5 eV below the Fermi-level at the Dirac point. The Fermi-level can be easily shifted inside this gap to make graphene a semiconductor which is crucial for graphene-based electronic devices. A graphene based p-n junction can be realized with graphene eptaxially grown on metal surface.
@article{arxiv.0712.4008,
title = {Graphene on metal surface: gap opening and n-doping},
author = {Y. H. Lu and P. M. He and Y. P. Feng},
journal= {arXiv preprint arXiv:0712.4008},
year = {2007}
}