Effect of B_2O_3 on the sintering and microwave dielectric properties of M-phase LiNb_(0.6)Ti_(0.5)O_3 ceramics

摘要

The effect of B_2O_3 addition on the sintering, microstructure and the microwave dielectric properties of LiNb_(0.6)Ti_(0.5)O_3 ceramics have been investigated. It is found that low-level doping of B_2O_3 (<2wt. percent) can significantly improve the densification and dielectric properties of LiNb_(0.6)Ti_(0.5)O_3 ceramics. Due to the liquid phase effect of B_2O_3 addition. LiNb_(0.6)Ti_(0.5)O_3 ceramics could be sintered to a theoretical density higher than 95 percent even at 880 deg C. No secondary phase was observed for the B2O3-doped ceramics. There is no obvious degradation in dielectric properties for the ceramics with B_2O_3 additions. In the case of 1 wt. percent B_2O_3 addition, the ceramics sintered at 880 deg C show good microwave dielectric properties of epsilon_r = 70. 2 Q x f= 5400 GHz, tau_f = -6.39 ppm/deg C. It represents that the ceramics could be promising for multilayer low-temperature co-fired ceramics (LTCC) applications.