Microwave dielectric properties and microstructures of V₂O₅-modified Zr_0.8Sn_0.2TiO₄ ceramics

The effects of V₂O₅ addition on the microwave dielectric properties and the microstructures of (Zr_0.8, Sn_0.2)TiO₄ ceramics been investigated. It is found that low-level doping of ZnO (1 wt%) and V₂O₅ (up to 2 wt%) can significantly improve the densification ability and the dielectric properties of (Zr_0.8, Sn_0.2)TiO₄ ceramics. (Zr_0.8, Sn_0.2)TiO₄ ceramics with additives could be sintered to a theoretical density higher than 95% at 1300°C due to the liquid-phase effect of V₂O₅ addition. The dielectric constant (ε_r) increased with increasing sintering temperature and saturated at 1300°C. The temperature coefficient of resonant frequency (τ_f) was not significantly affected while the unloaded quality factor Q was promoted by V₂O₅ addition. The ε_r value of 37.3, the Q × f value of 51500 (at 7 GHz) and the τ_f value of -2.1 ppm/°C were obtained for the 1 wt% ZnO-doped (Zr_0.8, Sn_0.2)TiO₄ ceramics with 1 wt% V₂O₅ addition sintered at 1300°C.