Single/few-layer boron nitride-based nanocomposites for high thermal conductivity underfills

Thermal management in 3D packaging plays an important role in the device performance and reliability. The development of thermally conductive underfills is highly crucial, but still challenging. In this work, single/few-layer boron nitride (BN) was exfoliated from bulk h-BN flakes and was incorporated into epoxy resin via a solvent transfer method. [1] The structure of exfoliated BN was characterized by varieties of techniques, including scanning electron microscopy, transmission electron microscopy, electron diffraction, Raman microscopy, and UV-vis microscopy. The single/few layer boron nitride/epoxy composite was characterized by thermomechanical analysis and thermogravimetric analysis. The thermal conductivity of exfoliated BN was measured by an infrared thermal imaging method. A significant enhancement of thermal conductivity (220%) is observed at a low filler loading of 5 wt%, indicating that the single/few-layer BN is a promising filler for the development of novel underfill for 3D packaging.