Coating dense silicon carbide layer on artificial graphites to achieve synergistically enhanced thermal conductivity and electronic insulation of polymer composites
Min Huang, Yexin Tian, Nizao Kong, Gen Liao, Chong Ye, Liqin Fu, Bingjie Wen, Kun Jia, Shuang Wang, Jinshui Liu, Fei Han
Abstract
Abstract As a potential thermal conductive filler, spherical graphite (SG) has high thermal conductivity, low density, and a good spherical shape structure. However, the poor electrical insulation of SG will seriously limit its application in highly integrated electronic device packaging. Herein, through a simple liquid–solid chemical reaction, the surface of the SG particle is firmly covered by a uniform silicon carbide (SiC) ceramic coating. Subsequently, a polycarbosilane precursor is immersed into the pore channels of the SiC layer and pyrolyzed at a high temperature to densify the coating. As compared to the original SG thermal pad, the SiC‐coated SG‐derived pad exhibits significantly enhanced electrical insulation and even higher thermal conductivity. As a result, the SiC‐coated SG‐based composite displays a high thermal conductivity of 3.36 W m −1 K −1 , a satisfactory resistivity of 7.10 × 10 10 Ω cm accompanied with a low density of 1.65 g/cm 3 . This work could provide the instructional designing protocol of the highly thermal conductive carbon‐based particles by coating ceramic layers for potential application in electronic packaging.