Effect of B2O3 addition on the microstructure and microwave dielectric properties of Li2CoTi3O8 ceramics

The effects of B2O3 addition on the sintering behavior, microstructure and microwave dielectric properties of the Li2CoTi3O8 ceramics were investigated. The variations of microstructure and composition of Li2CoTi3O8 ceramics were observed by the X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS) analysis. The small amount of B2O3 addition could not only effectively lower the sintering temperatures, but also reduce the temperature coefficient of resonant frequency (τf) of Li2CoTi3O8 ceramics. The Li2CoTi3O8 ceramic with 2.0 wt% B2O3 addition sintered at 900 °C exhibits good microwave dielectric properties with a εr of 26.6, a Q × f value of 21,300 GHz and a small τf of 1.78 ppm/°C. Moreover, B2O3-added Li2CoTi3O8 ceramic has a chemical compatibility with silver, which makes it a promising ceramic for LTCC technology application.