Improvement in adhesion strength of the cyanate ester resin composite material with high thermal conduction by addition of flexible Phenoxy resin

We investigated a low-cost resin composite material to replace ceramic in the insulated board in a power module. In order to apply the resin composite material to the insulated board, several traits are required: high heat dissipation, high heat resistance, and high adhesion strength with metals such as copper. In this paper, we report on our efforts to improve the heat resistance and adhesion strength in the resin composite material by preparing the material with a high percentage of the boron nitride (BN) filler. A cyanate ester resin with very high heat resistance was used for the base resin of the composite material, and it was blended with a flexible phenoxy resin. Consequently, we achieved a high thermal conductivity of 19W/ (m·K) in the resin composite material together with high heat resistance and high adhesion strength.