High frequency dielectric ceramic composition, dielectric resonator, dielectric filter, dielectric duplexer and communication apparatus

摘要

High frequency dielectric ceramic compositions having a dielectric constant ( epsilon r) of 30 to 50, a Q value of 15000 or more at 1 GHz, and a temperature-dependent factor of resonant frequency ( tau f) which can be arbitrarily controlled centering around 0 (ppm/ DEG C) can be obtained. The compositions have a main crystal of the perovskite type crystal phase, and are shown by (1-x)MeTiaO1+2a-xLn(Ma1/2Mb1/2)bO(3+3b)/2, wherein Ln is a rare earth element, Ma is at least one of Mg and Zn, Mb is at least one of Sn and Zr, Me is at least one of Ca and Sr, x is the mole fraction, and 0.950≤a≤1.050, 0.900≤b≤1.050, and 0.300≤x≤0.500.