High-Performance Printed Circuit Board Materials Based on Benzoxazine and Epoxy Blend System

Abstract

Epoxy resin has been used as an industrial printed circuit board (PCB) material based on its excellent mechanical strength and adhesion property to metal. Silica nanoparticle is employed as a component of hybrid matrix material with epoxy resin due to its superior electrical insulating properties. In this study, benzoxazine, which has attracted attention as a new generation of electrically insulating material and displays extraordinary thermal stability, was investigated as a candidate for PCB material. Benzoxazine and epoxy/silica nanoparticle hybrid films were prepared to achieve low dissipation factor and improved mechanical stability. Two types of benzoxazines, monobenzoxazine, and linear polybenzoxazine were investigated; for monobenzoxazine-based film, the blend with epoxy resin was required to improve physical property because monobenzoxazine film showed brittle nature which limited the application as a film with proper mechanical strength. Films with higher content of monobenzoxazine over epoxy resin resulted in lower dissipation factor around 0.005 frequency/10 GHz, however, the mechanical property of the film did not meet the condition as a PCB material. On the contrary, the linear polybenzoxazine-based film demonstrated enhanced mechanical stability but showed limitations in adhesion to the copper layer probably due to the lack of polar functional groups. To overcome the drawbacks, linear polybenzoxazine and epoxy blend systems were prepared to produce films with good adhesion and excellent electrical insulation property with the dissipation factor around 0.006 frequency/10 GHz.