Microwave dielectric properties of (Ba,Ca,Mg)O-Nd2O5-TiO2 ceramics

The microwave dielectric properties of 0.15(Ba1-xCax-mMgm)O-0.25Nd(2)O(3)-0.60TiO(2) were investigated for the development of a microwave dielectric material having a high dielectric constant, low dielectric loss and low temperature coefficient. As the amount of MgO increased, temperature coefficient of resonant frequency was degraded but dielectric loss was not so much affected. To enhance the dielectric constant and adjust zero temperature coefficient Bi2O3 was added to this system. These materials showed good dielectric properties such as epsilon(r)=86 similar to 89, Q . f(0) greater than or equal to 5000 and tau(f) congruent to 5 ppm/degrees C. The relationship between microstructures and dielectric properties was investigated By scanning electron microscopy.