Temperature dependence of the conductivity of graphene on boron nitride

The substrate material of monolayer graphene influences the charge carrier mobility by various mechanisms. At room temperature, the scattering of conduction electrons by phonon modes localized at the substrate surface can severely limit the charge carrier mobility. We here show that for substrates made of the piezoelectric hexagonal boron nitride (hBN), in comparison to the widely used SiO₂, this mechanism of remote phonon scattering is---at room temperature---weaker by almost an order of magnitude, and causes a resistivity of approximately 3 Ω. This makes hBN an excellent candidate material for future graphene-based electronic devices operating at room temperature.