Integration of polymer/ceramic thin film capacitor on PWB

Electrical properties of various polymer-ceramic composites have been studied for use in integrated capacitors on PWB substrates. The dielectric constant of the composite is strongly dependent on the individual properties of polymer and ceramic materials. Epoxy is the material of choice for its compatibility with PWBs. Further, epoxy materials are not attacked by high PH environment during electroless plating of the capacitor electrodes. Photodefinable and nonphotodefinable materials have been evaluated for capacitor integration on PWBs using thin-film processes and screen printing. Lead magnesium niobate is selected as the filler material for its high dielectric constant value and its compatibility with most polymers.