Microwave Dielectric Properties of the (1―x)(Mg0.9Co0.1)TiO3―x(Ca0.61La0.26)TiO3 Ceramics

The microwave dielectric properties of the (1―x)(Mg0.9Co0.1)TiO3―x(Ca0.61La0.26)TiO3(MCT―CLT) ceramics were investigated. The system was prepared using a conventional solid―state ceramic route. The objective of the present work is to compensate for the negative temperature coefficient of resonant frequency (τf) of (Mg0.9Co0.1)TiO3 (MCT) by the addition of (Ca0.61La0.26)TiO3 (CLT). The microwave dielectric properties are strongly correlated with the sintering temperature and the composition. Very dense MCT―CLT ceramics were prepared by sintering at 1300 . When the ceramics were sintered at temperatures above 1300 , the bulk density decreased and the dielectric properties deteriorated. With the increasing of x, the relative dielectric constant (εr) of the ceramics increases and the product of quality factor and resonant frequency (Q×f) decreases. For practical application, 0.87(Mg0.9Co0.1)TiO3― 0.13(Ca0.61La0.26)TiO3 (87MCT―13CLT) ceramics sintered at 1300 with a dielectric constant εr=22.4, a Q×f value of 35000 GHz and a temperature coefficient of resonance frequency (τf) of ―8.7×10―6/ was proposed in this paper.