Low temperature sintering of Ca[(Li1/3Nb2/3)(1-x)Ti-x]O3-delta based microwave dielectric ceramics with glass frit

Abstract

The microstructures. and the microwave dielectric properties of Ca[(Li1/3Nb2/3)(1-x)Ti-x]O3-delta (CLNT) ceramics with different amount of glass frit additions were investigated. Addition of glass frit(B2O3-ZnO-SiO2-PbO system) improved the densification and decreased the sintering temperature from 1150 degrees C to 900 degrees C of Ca[(Li1/3Nb2/3)(1-x)Ti-x]O3-delta microwave dielectric ceramics. The dielectric constants (epsilon(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 (tau(f)) shifted positive value as glass contents were increased. The dielectric proper-ties of Ca[(Li1/3Nb2/3)(0.8)Ti-0.2]O3-delta with 12 wt% glass sintered at 900 degrees C for 3 h were epsilon(r) = 40, Q (.) f(0) = 12, 500, tau(f) = -8ppm/degrees C, 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).