Structural properties for the substitution of Ta⁵⁺ ions in the BaTiO₃ crystal lattice were observed by SEM/EDS. The formation of perovskite phase and the change of (111), (200) and (002) planes of BaTiO₃ solid solution containing a small amount of Ta⁵⁺ were studied. As a result, the relationship between the dielectric properties and the polycrystalline structure of Ta⁵⁺-doped BaTiO₃ was confirmed. It was found that the maximum dielectric constant of the Ta⁵⁺-doped BaTiO₃ solid solution was more than about 8000, and the transition temperature shifted slightly toward the lower temperature as compared with the pure BaTiO₃. The dielectric constants of all the samples measured in the temperature region above the transition temperature showed some diffusivity and satisfied the modified Curie-Weiss law.

PACS numbers: 77.12, 77.64, 77.81

Keywords: Ta⁵⁺-doped BaTiO₃, Dielectric properties, Modified Curie-Weiss law