Compositional Design of Lead-Free, Low-Temperature Cofired Ceramic Dielectric Composite

Abstract

Compositional design and properties of a lead-free, low-temperature cofired ceramic (LTCC) system containing a crystallizable K2O–CaO–SrO–BaO–B2O3–SiO2 glass, alumina and titania have been investigated. The ternary composites with a high sintered density of >95% can be obtained at 875 °C. Compositions with tailor-made properties are designed according to a working model based on the assumption of the mixing rule, and validated with experimental results. The resulting lead-free composites exhibit a dielectric constant of 7.7–20.0 at 1 MHz, and a thermal expansion coefficient of (5.37–7.22)×10-6/°C.