Novel Temperature Stable Li 2 MnO 3 Dielectric Ceramics with High Q for LTCC Applications

Novel microwave dielectric ceramics in the Li 2 MnO 3 system with high Q prepared through a conventional solid‐state route had been investigated. All the specimens exhibited single phase ceramics sintered in the temperature range 1140°C–1230°C. The microwave dielectric properties of Li 2 MnO 3 ceramics were strongly correlated with sintering temperature and density. The best microwave dielectric properties of ε r  = 13.6, Q × f  =   97 000 (GHz), and τ f  = −5.2 ppm/°C could be obtained as sintered at 1200°C for 4 h. BaCu ( B 2 O 5 ) ( BCB ) could effectively lower the sintering temperature from 1200°C to 930°C and slightly induced degradation of the microwave dielectric properties. The Li 2 MnO 3 ceramics doped with 2 wt% BaCu ( B 2 O 5 ) had excellent dielectric properties of ε r  = 11.9, Q × f  =   80 600 (GHz), and τ f  = 0 ppm/°C. With low sintering temperature and good dielectric properties, the BCB added Li 2 MnO 3 ceramics are suitable candidates for LTCC applications in wireless communication system.