Low Temperature Sintering of Ca[(Li_(1/3)Nb_(2/3))_(1-x)Ti_x]O_(3-δ) Based Microwave Dielectric Ceramics with Glass Frit

摘要

The microstructures and the microwave dielectric properties of Ca[(Li_(1/3)Nb_(2/3))_(1-x)Ti_x]O_(3-δ) (CLNT) ceramics with different amount of glass frit additions were investigated. Addition of glass frit(B_2O_3-ZnO-SiO_2-PbO system) improved the densification and decreased the sintering temperature from 1150℃ to 900℃ of Ca[(Li_(1/3)Nb_(2/3))_(1-x)Ti_x]O_(3-δ) microwave dielectric ceramics. The dielectric constants (ε_r) and bulk density were increased, as increasing glass contents from 10 wt% to 15 wt%. The quality factor (Q · f_0), however, was decreased slightly. The temperature coefficients of the resonant frequency (τ_f) shifted positive value as glass contents were increased. The dielectric properties of Ca[(Li_(1/3)Nb_(2/3))_(0.8)Ti_(0.2)]O_(3-δ) with 12 wt% glass sintered at 900℃ for 3 h were ε_r = 40, Q · f_0 = 12,500, 觃f = -3 ppm/℃, respectively. The relationship between the microstructure and dielectric properties of ceramics was studied by X-ray diffraction (XRD), energy dispersive spectroscopy (EDS) and scanning electron microscopy (SEM).