State Key Laboratory Breeding Base of Nonferrous metals and specific Materials Processing, Key laboratory of Nonferrous Materials and New Processing Technology, Ministry of Education, College of Material Science and Engineering, Guilin University of Technology, Guilin 541004, China
A novel low-firing microwave dielectric ceramic NaCa2Mg2V3O12 was prepared by the conventional solid state ceramic route. The phase composition, microstructure, and sintering behavior were investigated. The NaCa2Mg2V3O12 ceramic could be well densified at around 915 °C and exhibited favorable microwave dielectric properties with a low relative permittivity of ∼10, a high quality factor (Q Qu×f ) of ∼50 600 GHz, and a negative temperature coefficient of resonant frequency (τf ) of −47 ppm/°C. The NaCa2Mg2V3O12 ceramic can be compatible with Ag electrode, which makes it a promising ceramic for LTCC technology application. CaTiO3 was added into the NaCa2Mg2V3O12 ceramic to obtain a near zero τf, and 0.8NaCa2Mg2V3O12-0.2CaTiO3 ceramic sintered at 930 °C for 4 h showed improved properties with εr=11.5, Qu×f=37 500 GHz, and τf=2 ppm/°C.
