Liquid metal-based thermal interface materials with a high thermal conductivity for electronic cooling and bioheat-transfer applications

Effective heat transfer is imperative in devices with high power densities, for which thermal interface materials (TIMs) may be used to improve heat conduction across interfaces. Compared to conventional TIMs such as thermal grease and solder, liquid metal (LM) TIMs offer several advantages owing to their intrinsically high thermal and electrical conductivities, flexibility, and low melting points. Moreover, their unique properties, such as a low vapor pressure, subcooling, and biocompatibility, enable their application in thermal management and biomedical therapy. This review provides a basic understanding of LM-based TIMs by discussing their fundamental characteristics and correlative theories. Several representative applications of LM TIMs in electrical devices, soft electronics, and bio-heat transfer are presented. Furthermore, the challenges facing these materials are highlighted and their future application prospects are delineated to present the readers with a comprehensive overview of this class of materials.