The polarization relaxations and decreasing dielectric loss in (In0.5Ta0.5)0.1Ti0.9O2 ceramics via anion substitution

With the rapid development of integrated circuits and microelectronic devices, the research of colossal dielectric constant ceramics has been greatly promoted. In this study, (In _0.5Ta _0.5) _0.1Ti _0.9O _2-xF _x ( x = 0, 0.03, 0.06, and 0.09) ceramics were synthesized using a conventional solid-phase sintering method in an Air atmosphere. When the concentration is 0.06, the colossal dielectric constant (ε = 10 ⁵ ) and dielectric loss (tan δ = 0.068) were obtained at 1 kHz. The impedance spectra confirm that the materials have semiconductor grains and insulating grain boundaries, which originates from polaron polarization and electron hopping polarization. Meanwhile, the generation of oxygen vacancies ( V O · · ) is restricted because of the F ⁻ substitutional O ²⁻ sites, increasing the grain boundaries resistance and leading to low dielectric loss. Therefore, this anion doping method can be used as a simple and scalable way to provide new ideas to further progress the requirements of dielectric materials for integrated electronics.