Thermal boundary resistance between the polycrystalline graphene and the amorphous SiO2 substrate

Abstract

The interface between graphene and substrate plays a very important role in graphene-based advanced devices. We examine the thermal boundary resistance R of the graphene/silicon dioxide (Gr/SiO2) interface by using molecular dynamics simulations. R decreases monotonically with the increase of temperature and exhibits a strong dependence on the substrate coupling strength. Due to the polycrystalline nature of graphene, we show that the presence of periodic 5–7, 5–8–5 and 5–7–5–7 grain boundaries in graphene enhances phonon transmission across the Gr/SiO2 interface, which are attributed to both the increased overlap in the phonon spectra and more inelastic scattering at the interface.