A wood-inspired epoxy-based electronic packaging material with vertically aligned thermally conductive channels for electromagnetic waves absorption and thermal management

Abstract

Multifunctional materials integrating electromagnetic waves absorption (EMA) and heat conductivity functions are urgently desirable to tackle the heat emission and electromagnetic interference issues of advanced electronics. However, simultaneously mustering these features into one material remains a formidable challenge as the incompatibility between high thermal conductivity and excellent EMA performance. Herein, inspired by the water transport process of trees in nature, an epoxy-based electronic packaging material (CFS/EB) with vertical thermal conduction channels is fabricated by encapsulating high thermal conductivity boron nitride/epoxy hybrids into aerogel skeleton with good electromagnetic features. This ingenious design not only can defuse the issue of difficult coexistence of outstanding EMA and thermal conduction performance, but also delivers high through-plane thermal conductivity arised from vertical aligned channels. The resulting CFS/EB composite exhibits strong EMA performance with minimum reflection loss value of −59.2 dB and broad effective absorption bandwidth of 5.82 GHz. Synchronously, the composite also holds the high through-plane thermal conductivity of 1.51 W m−1 K−1 (655 % higher than pure epoxy resin) at low filler loading of 13.15 wt% as well as electrical insulation of 1.43 × 1012 Ω·cm. Such a superior comprehensive performance endows CFS/EB composite a great application prospects in electronic packaging fields, whilst the orientation structure design triggered by this bioinspired strategy offer facile yet feasible alternatives to address heat accumulation and electromagnetic interference problems for integrated electronics.