Novel polymer-ceramic nanocomposite based on high dielectric constant epoxy formula for embedded capacitor application

Embedded capacitor technology can increase silicon packing efficiency, improve electrical performance, and reduce assembly cost compared with traditional discrete capacitor technology. Developing a suitable material that satisfies electrical, reliability, and processing requirements is one of the major challenges of incorporating capacitors into a printed wiring board (PWB). Polymer-ceramic composites have been of great interest as embedded capacitor material because they combine the processability of polymers with the high dielectric constant of ceramics. A novel nanostructure polymer-ceramic composite with a very high dielectric constant (epsilon (r) similar to 110, a new record for the highest reported epsilon (r) value of a nanocomposite) was developed in this work. A high dielectric constant is obtained by increasing the dielectric constant of the epoxy matrix (epsilon (r) > 6) and using the combination of lead magnesium niobate-lead titanate (PMN-PT)/BaTiO3 as the ceramic filler. This nanocomposite has a low curing temperature (<200C); thus, it is multichip-module laminate (MCM-L) process-compatible. An embedded capacitor prototype with a capacitance density of 50 nF/cm(2) was manufactured using this nanocomposite and spin-coating technology. The effect of the composite microstructure on the effective dielectric constant was studied. This novel nanocomposite can be used for integral capacitors in PWBs. (C) 2002 John Wiley & Sons, Inc.