Ceramics Fillers in Dielectric Composites for High Frequency Applications

Abstract

Recent development of high frequency technologies induces strong demands for better dielectric substrate materials with adequate dielectric constant and low dielectric loss. Polymer-based composites filled with high-Q ceramics fillers are the promising candidates for such applications. Magnesium oxide (MgO) and hexagonal boron nitride (hBN) particles were studied as high-Q ceramics fillers. Both fillers were found to be suitable as constituents of low loss composites. In the case of MgO, it was found that the particle size affected the tan δvalues of composites and larger particle, typically on the order of micrometer, was required to obtain low loss composites. Anisotropic shape of the fillers was effective to improve the temperature dependent properties of the composites.