Microwave dielectric properties of LTCC materials consisting of glass–Ba2Ti9O20 composites

Interaction between Ba2Ti9O20 microwave dielectric ceramics and BaBSiO glass materials was systematically investigated. BaTi(BO3)2 intermediate phase was induced and its proportion increased with firing temperature. Fortunately, the formed BaTi(BO3)2 phase does not result in marked degradation on the microwave dielectric properties of the Ba2Ti9O20–BaBSiO composite materials. Good microwave dielectric properties (K=13.2, Q×F=1150) were obtained by firing the Ba2Ti9O20–BaBSiO (50:50 vol.%) materials at 900 °C for 30 min. Precoating a thin layer of BaTi(BO3)2 materials on the Ba2Ti9O20 powders prior to processing of the ceramic tapes can markedly suppress the interaction between the Ba2Ti9O20 and BaBSiO glass, significantly improving the consistency of the microwave dielectric properties for the low temperature cofirable ceramic (LTCC) materials.