Effect of interfacial layer incorporation in electroplated copper-graphene composites on thermal conductivity

In this study, we successfully fabricated graphene/metal composites with high isotropic thermal conductivities. To address the thermal anisotropy resulting from the mismatch between the in-plane and through-plane thermal conductivities of multilayer graphene, we synthesized graphene foam (GF) with a three-dimensional structure. A homogeneous Cu layer was deposited by electroplating on the GF surface, filling the pores. Following the removal of pores in the composites through a spark plasma sintering process, the thermal conductivity of Cu-GF containing only 0.15 vol% of graphene was found to be significantly enhanced, with an increase of similar to 9 % compared to that of electroplated Cu. The incorporation of a thin Ti layer into the composites resulted in a higher Cu plating rate and achieved a ratio of 1.01 between the in-plane and through-plane thermal conductivities. These results are expected to be effectively applied in the advanced electronics industry, in which a high heat dissipation capacity is a crucial requirement.