Heat-resistant epoxy-silicon hybrid materials for printed wiring boards

An epoxy-silicon hybrid resin based on a new concept has been developed. This resin has a structure in which epoxy-silicon oligomers by sol-gel reaction are incorporated into the epoxy resin matrix at the nanometer level. The nanostructure was confirmed by ²⁹Si NMR spectrum and a time-resolved energy filtering-transmission electron microscopy technique. This epoxy-silicon hybrid resin shows excellent mechanical properties at high temperatures. The elastic modulus at 260°C was 0.6 GPa, much higher than the 0.08 GPa of conventional epoxy resins; and the thermal expansion coefficient above the glass transition temperature was two-thirds of the conventional one. It was confirmed that conventional fabrication process for FR-5 was applicable to copper clad laminates for the epoxy-silicon hybrid resin.