MICROWAVE DIELECTRIC CERAMIC COMPOSITION

摘要

A microwave dielectric ceramic composition exhibiting excellent relative permitting ( epsilon ) and high Qf-value, enabling the temperature coefficient of resonance frequency to be easily adjusted, and being best suited for a filter having cavities made of, e.g., iron or copper exhibiting a large temperature coefficient of resonance frequency. The ceramic is of a BaO-TiO2-Nd2O3-Sm2O3 ceramic, type wherein Nd2O3 is partly substituted by Bi2O3, Nd2O3 is partly substituted by Ln2O3 (where Ln is La, Ce or Pr) and, the above substituted Ln2O3 is partly substituted by Eu2O3 to improve the properties so that epsilon is 82.5 to 92.5, Qf is 6000 to 7300 GHz and tau f is 10 -20 ppm/ DEG C. This makes it possible to impart favorable electric characteristics to resonance cavities of various materials and sizes.