Influence of ZnO additions to 0.96Mg0.95Co0.05TiO3–0.04SrTiO3 ceramics on sintering behavior and microwave dielectric properties

Abstract The effects of ZnO addition on the microstructures and microwave dielectric properties of 0.96Mg 0.95 Co 0.05 TiO 3 –0.04SrTiO 3 ceramics were investigated. ZnO was selected as liquid phase sintering aids to lower the sintering temperature of 0.96Mg 0.95 Co 0.05 TiO 3 –0.04SrTiO 3 ceramics. With ZnO additives, the densification temperature of 0.96Mg 0.95 Co 0.05 TiO 3 –0.04SrTiO 3 can be effectively reduced from 1450 °C to 1250–1350 °C. The crystalline phase exhibited no phase difference at low addition levels (0.5–4 wt%). It is found that low-level doping of ZnO (0.5–4 wt%) can significantly improve the density and dielectric properties of 0.96Mg 0.95 Co 0.05 TiO 3 –0.04SrTiO 3 ceramics. The quality factors Q × f was strongly dependent upon the amount of additives. Q × f values of 74,000 GHz and 30,000 GHz could be obtained at 1250–1350 °C with 1 wt% and 4 wt% ZnO additives, respectively. During all additives ranges, the relative dielectric constants were not significantly different and ranged from 20.1 to 27.77. The temperature coefficient varies from −8 ppm/°C to 2.7 ppm/°C.