Investigation on thermal conductivity of graphene/Si heterostructure based on molecular dynamics simulation

Abstract

The effect of doping and defects on thermal conductivity of Graphene/Si interface structure based on molecular dynamics simulation is investigated. With the nitrogen and boron doping defect ration increasing, the thermal conductivity of heterostructure shows decline trend. But the boron doping effect to thermal conductivity of heterostructure is higher than that of nitrogen doping. It is analyzed that due to the mass of nitrogen and boron is different, the harmonic effect of lattice vibration happens to some extent. The interfacial thermal conductivity decreases monotonously with hydrogenation rate. Hydrogenated graphene has a greater influence on the thermal conductivity in Zigzag direction. When the hydrogenation rate reaches 5%, the thermal conductivity decreases to 77.8 W/mK. Intrinsic defects of graphene will greatly reduce the thermal conductivity of single-layer graphene/Si interface, and single vacancy defects have the greatest influence on thermal conductivity. It builds a basis for future work on progress investigation of thermal property of graphene film heterostructure.