The microstructures and the microwave dielectric properties of the (1 - x)Mg0.95Co0.05TiO3 - xZn0.975Ca0.025TiO3 ceramic system prepared using the conventional solid state method were investigated. In order to achieve a temperature-stable material, a method of combining a positive temperature coefficient material with a negative one studied. Zn0.975Ca0.025TiO3 has dielectric a constant εr ∼ 30, Q × f value ∼ 45,000 GHz, and a large positive τf value ∼ 30 ppm/°C. Mg0.95Co0.05TiO3 has a high dielectric constant (εr ∼ 16.8), high quality factor (Q × f value ∼ 230,000 at 10 GHz), and a negative τf value (-54 ppm/°C). The dielectric constant decreased from 29.1 to 18.36 when x changed from 0.9 to 0.3. In the x(Mg0.95Zn0.05Ti)O3 - (1 - x)Zn0.975Ca0.025TiO3 system, the microwave dielectric properties can be effectively controlled by varying the x value. At 1200 °C, 0.7Mg0.95Co0.05TiO3 - 0.3 Zn0.975Ca0.025TiO3 had a dielectric constant (εr) of 22.6, a Q × f value of 57,000 GHz, and a temperature coefficient of resonant frequency (τf) of 0 ppm/°C.
All Science Journal Classification (ASJC) codes
- Mechanics of Materials
- Mechanical Engineering
- Metals and Alloys
- Materials Chemistry