Effect of CaTiO3 addition on microwave dielectric properties of Mg2(Ti0.95Sn0.05)O4 ceramics

The microwave dielectric properties of CaTiO3-added Mg2(Ti0.95Sn0.05)O4 ceramics prepared by the mixed oxide route have been investigated. The combination of spinel-structured Mg2(Ti0.95Sn0.05)O4 and perovskite-structured CaTiO3 forms a two-phase system (1 − x)Mg2(Ti0.95Sn0.05)O4–xCaTiO3, which was confirmed by the XRD patterns and the EDX analysis and it also leads to a zero τf. The microwave dielectric properties of the ceramics can be effectively controlled by varying the x value. For practical applications, a new microwave dielectric material 0.91Mg2(Ti0.95Sn0.05)O4–0.09CaTiO3 is suggested and it possesses a good combination of dielectric properties with an ɛr of ∼18.01, a Q × f of ∼92,000 GHz, and a τf of ∼0 ppm/°C, which makes it is a very promising candidate material for high frequency applications.