Thermally conductive graphene-based films for high heat flux dissipation

Abstract

Heat accumulation during the operation of semiconductor devices is fatal to the stability and longevity of high-performance electronic systems. Heat spreaders are critical for transferring excess heat away from heat-producing regions to surroundings. Recently, the assembly of two-dimensional graphene sheets into macroscopic graphene-based films exhibiting superior in-plane thermal conductivity (k) has garnered considerable interest in academia. These films have been applied as heat spreaders in the thermal management of portable electronic devices. While increasing k values is paramount for enhancing the heat transmissibility of graphene-based films, the significance of film thickness (d) in this regard has been largely overlooked. This paper reviews the research progress in preparing high-heat-transmissibility graphene-based films, shedding light on the critical yet previously neglected influence of d and its intricate relationship with k. Advancements in increasing k values are discussed, focusing on strategies and related mechanisms for controlling structural defects in graphene-based films. Building upon these insights, difficulties associated with the controlled assembly of thick graphene-based films are elucidated and existing efforts to mitigate the pronounced decrease in k with increasing d are presented. Finally, major challenges and potential solutions to current bottlenecks are proposed to guide the future development of high-heat-transmissibility graphene-based films.