Characterization and Dielectric Behavior of (1-x)Mg(Zr_0.05Ti_0.95)O₃−xCaTiO₃ Ceramic System at Microwave Frequency

Abstract

The microstructures and the microwave dielectric properties of the (1-x)Mg (Zr_0.05Ti_0.95)O₃−xCaTiO₃ ceramic system were investigated. In order to achieve a temperature-stable material, compositions in the (1-x)Mg(Zr_0.05Ti_0.95)O₃−xCaTiO₃ system which the CaTiO₃ (τ_f ∼ +800 ppm/°C) was chosen as a τ_f compensator and added to Mg(Zr_0.05Ti_0.95)O₃ (τ_f ∼ −50 ppm/°C) to form a two phase system were designed to compensate the negative temperature coefficient of the resonant frequency of Mg(Zr_0.05Ti_0.95)O₃. By appropriately adjusting the x-value in the (1-x)Mg (Zr_0.05Ti_0.95)O₃−xCaTiO₃ ceramic system, near-zero τ_f value can be achieved. A new microwave dielectric material system, 0.92Mg(Zr_0.05Ti_0.95)O₃−0.08CaTiO₃ applicable in microwave devices is suggested and possesses the optimum dielectric properties of a dielectric constant ϵ_r ∼ 22.3, a Q × f value ∼ 100,000 (GHz) and a τ_f value ∼ 5 ppm/°C.

Keywords:

• (1-x)Mg(Zr_0.05Ti_0.95)O₃−xCaTiO₃ ceramics
• Microwave dielectric properties

Acknowledgment

This work was supported by the National Science Council of the Republic of China under grant NSC101-2622-E-239-002-CC3.