Experimental Investigations on Thermal Transport Properties of Nanoscale-Graphite-Film

Accurately and directly characterizing the thermal properties of graphene and thin-graphite films (GFs) is of fundamental importance for understanding the heat transport mechanism and of practical interest in possible applications of thermal management. However, due to the lack of experiment data, the mechanism of the thickness dependence of GFs thermal properties has not been fully understood yet. In this study, a 90-nm-thick GF is characterized by the time-domain thermoreflectance method, and the obtained GFs in-plane thermal conductivity and interfacial thermal conductance between GFs and gold are (1354 +/- 297) W/(m center dot K) and (38 +/- 6) MW/(m(2)center dot K), respectively. Two theoretical models are also applied for comparison and discussion, and we conclude that the influence from the surface perturbation by supporting materials on the phonon transport of graphite nano-films will beyond the near surface layers to the more inner ones. This work not only provides a better understanding of the fundamental mechanisms of the thermal transport size effect in GFs, but also facilitates the possible applications of GFs as heat spreaders in the future.

Automated summary

Accurate and direct characterization of the thermal properties of graphene and thin-graphite films (GFs) is important for understanding their heat transport mechanism and potential applications in thermal management. However, the mechanism of the thickness dependence of GFs thermal properties has not been fully understood due to the lack of experimental data. In this study, a 90-nm-thick GF was characterized using the time-domain thermoreflectance method, and its in-plane thermal conductivity and interfacial thermal conductance with gold were obtained. Two theoretical models were also applied for comparison and discussion, concluding that the influence of surface perturbation on phonon transport extends beyond the near surface layers. This work enhances our understanding of the thermal transport size effect in GFs and facilitates their future applications as heat spreaders.