Temperature compensation effects of TiO2 on Ca[Li1/3Nb2/3)0.8Sn0.2]O3-δ microwave dielectric ceramic

The crystal structure and dielectric properties of TiO2-modified Ca[(Li1/3Nb2/3)(0.8) Sn-0.2]O3-delta microwave ceramics are investigated in the present paper. The crystal structure is probed by XRD patterns and their Rietveld refinement, results show that a single perovskite phase is formed in TiO2-modified Ca[(Li1/3Nb2/3)(0.8)Sn-0.2]O3-delta ceramics with the crystal structure belonging to the orthorhombic Pbnm 62 space group. Raman spectra results indicate that the B-site order disorder structure transition is a key point to the dielectric loss of TiO2-modified Ca[(Li1/3Nb2/3)(0.8)Sn-0.2]O3-delta ceramics at microwave frequencies. After properly modified by Ti02, the large negative temperature coefficient of Ca[(Li1/3Nb2/3)(0.8)Sn-0.2]O3-delta ceramic can be compensated and the optimal microwave dielectric properties can reach epsilon(r) = 25.66, Q(f) = 18,894 GHz and TCF = -6.3 ppm/ degrees C when sintered at 1170 degrees C for 2.5 h, which manifests itself for potential use in microwave dielectric devices for modern wireless communication.