Evidence for semiconducting behavior with a narrow band gap of Bernal graphite

Abstract

We have studied the resistance of a large number of highly oriented graphite samples with areas ranging from several mm 2 to a few μm 2 and thickness from ∼10 nm to several tens of micrometers. The measured resistance can be explained by the parallel contribution of semiconducting graphene layers with low carrier density < 10 9 cm -2 and the one from metallic-like internal interfaces. The results indicate that ideal graphite with Bernal stacking structure is a semiconductor with a narrow band gap E g ∼ 40 meV. © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.