Comparison of theoretical predictions and experimental values of the dielectric constant of epoxy/BaTiO3 composite embedded capacitor films

Polymer/ceramic composites are the most promising embedded capacitor material for organic substrates application. Predicting the effective dielectric constant of polymer/ceramic composites is very important for design of composite materials. In this paper, we measured the dielectric constant of epoxy/BaTiO3 composite embedded capacitor films with various BaTiO3 particles loading for 5 different sizes BaTiO3 powders. Experimental data were fitted to several theoretical equations to find the equation useful for the prediction of the effective dielectric constant of polymer/ceramic composites and also to estimate the dielectric constant of BaTiO3 powders. The Lichtenecker equation and the Jayasundere-Smith equation were useful for the prediction of the effective dielectric constant of epoxy/BaTiO3 composites. And calculated dielectric constants of the BaTiO3 powders were in the range of 100 to 600, which were lower than the dielectric constant of BaTiO3 bulk ceramics probably due to the presence of voids or pores. (C) 2005 Springer Science + Business Media, Inc.