Constructing phonon transport bridges via low-temperature sintering in Diamond@Ag/EP composite to achieve efficient 3D networks structure

The rapid advancement of integrated circuits and electronic devices presents challenges to traditional epoxy molding compound (EMC), necessitating the demand for highly thermally conductive yet electrically insulating composites to address the “hotspot issues” in high-power chips. Here, a low-temperature sintering technology based on metal–organic decomposition is developed to fabricate a three-dimensional interconnected networks structure composite (3D-Diamond@Ag/EP). The in-situ decomposition of the silver amine complex on the surface of the Diamond@Ag hybrid filler forms nano-silver bridges, which facilitate the successful construction of the three-dimensional networks structure. When the Ag reaches 4.0 vol%, the thermal conductivity of the composite (reaches 6.42 W/m·K) breaks out of the low numerical blockade of the epoxy resin (0.18 W/m·K), while maintaining excellent insulation performance. It is noteworthy that the great improvement of thermal conductivity is achieved by the synergistic effect of sufficient thermal pathways and minimizing interfacial thermal resistance along these paths. Moreover, this work obtained composite exhibits other excellent thermal characteristics. It provided a practical route to produce high thermal conductivity polymer-based composites with electrical insulation for heat management in modern electronic devices.