Enhancing Thermal\nManagement of Graphene Devices by\nSelf-Assembled Monolayers

Two-dimensional graphene has emerged as a promising competitor\nto silicon in the post-Moore era due to its superior electrical, optical,\nand thermal properties. However, graphene undergoes a strong degradation\nin its in-plane thermal conductivity when it is coupled to an amorphous\nsubstrate. Meanwhile, the weak van der Waals interaction between graphene\nand the dielectric substrate leads to high interfacial thermal resistance.\nSevere challenges in the device’s heat dissipation rise, resulting\nin elevated hotspot and deteriorated electrical performance. Here,\nwe applied self-assembled monolayers (SAMs) to modify the interface\nbetween graphene and the oxide substrate and mitigate the thermal\nissues in the device. The −NH<sub>2</sub> terminated SAM demonstrates\nenhanced interfacial coupling strength between graphene and substrate,\nincreasing the interfacial thermal conductance. The −CH<sub>3</sub> terminated SAM effectively suppresses the substrate phonon\nscattering, preserving the high in-plane thermal conductivity of graphene.\nParticularly, the −NH<sub>2</sub> terminated SAM significantly\nenhances the heat dissipation efficacy of graphene field-effect transistors\nand alleviates the self-heating issues. Enhancements of 28.1% and\n48.2% were observed in the devices’ current-carrying capacity\nand maximum power density<sub>,</sub> respectively. Our research provides\na highly attractive platform for incorporating SAMs to improve thermal\nmanagement in two-dimensional electronic devices.