Structure and dielectric characterization of xNd(Mg1/2Ti1/2)O3-(1-x) Ca0.6La0.8/3TiO3 in the microwave frequency range

The crystal structures, phase compositions and the microwave dielectric properties of the xLa(Mg1/2Ti1/2)O-3-(1-x)Ca0.8Sr0.2TiO3 composites prepared by the conventional solid state route have been investigated. The formation of solid solution is confirmed by the XRD patterns. Doping with B2O3 (0.5 wt.%) can effectively promote the densification and the dielectric properties of xNd(Mg1/2Ti1/2)O-3-(1-x)Ca0.6La0.8/3TiO3 ceramics. It is found that xNd(Mg1/2Ti1/2)O-3-(1-x)Ca0.6La0.8/3TiO3 ceramics can be sintered at 1375 degrees C, due to the liquid phase effect of B2O3 addition observed by Scanning Electronic Microscopy. At 1375 degrees C, 0.4Nd(Mg1/2Ti1/2)O-3-0.6Ca(0.6)La(0.8/3)TiO(3) ceramics with 1 wt.% B2O3 addition possesses a dielectric constant (epsilon(r)) of 49, a Q x f value of 13,000 (at 8 GHz) and a temperature coefficients of resonant frequency (tau(f)) of 1 ppm/degrees C. As the content of Nd(Mg1/2Ti1/2)O-3 increases, the highest Q x f value of 20,000GHz for x = 0.9 is achieved at the sintering temperature 1400 degrees C. (C) 2011 Elsevier B.V. All rights reserved.