Ultralow sintering temperature and permittivity with excellent thermal stability in novel borate glass-ceramics

A novel CuO-ZnO-B2O3-Li2O glass-ceramic was prepared by solid phase method, and. Its phase transition, sintering and dielectric performance was studied. No crystalline phase is observed for the specimen sintered at 560 °C. However, the samples sintered at 580 °C and 600 °C, consist of ZnB4O7 and Cu2B4O7. And the Li2CuB4O8 appears with further increasing temperature. The εr and τf change slightly but the Q × f value alter greatly with firing temperature. The glass-ceramic fired at 620 °C possesses optimum properties with εr = 3.33, Q × f = 17,724 GHz and τf ≈ 0 ppm/°C. Furthermore, the as-prepared glass-ceramic exhibits good co-firing compatibility with Ag and Al electrode. These properties qualify the dielectric material as promising alternatives for wireless communication applications.