New dielectric material system of x(Mg0.95Zn0.05Ti)O3–(1 − x)Ca0.8Sm0.4/3TiO3 at microwave frequency

The microstructures and the microwave dielectric properties of the x(Mg0.95Zn0.05)TiO3–(1 − x) Ca0.8Sm0.4/3TiO3 ceramic system were investigated. In order to achieve a temperature-stable material, we studied a method of combining a positive temperature coefficient material with a negative one. Ca0.8Sm0.4/3TiO3 has dielectric properties of dielectric constant εr ~ 120, Q × f value ~ 13,800 GHz and a large positive τf value ~ 400 ppm/°C. (Mg0.95Zn0.05)TiO3 possesses high dielectric constant (εr ~ 16.21), high quality factor (Q × f value ~ 210,000 at 9 GHz) and negative τf value (− 59 ppm/°C). Sintering at 1300 °C with x = 0.9, 0.9(Mg0.95Zn0.05Ti)O3 − 0.1 Ca0.8Sm0.4/3TiO3 has a dielectric constant (εr) of 22.7, a Q × f value of 124,000 GHz and a temperature coefficient of resonant frequency (τf) of − 6.3 ppm/°C.