Microstructure, Optical Properties, and Dielectric Properties of Film Ceramics BaTiO3−BaZr0.5Ti0.5O3 for High-Temperature Capacitors

Ceramics composed of (0.1)BaTiO3–(0.9)BaZr0.5Ti0.5O3 have been synthesized to fulfill the specifications required for multilayer ceramic capacitors. This study investigates the influence of various annealing temperatures on the materials' microstructure, optical properties, and dielectric characteristics. Findings indicate that elevated annealing temperatures enhance crystallinity, grain size, dielectric constant, and capacitance. Notably, samples annealed at 800 °C demonstrate high crystallinity, increased grain size, a reduced energy band gap (Eg ≈ 3.50 eV), an optimal dielectric constant of approximately 80,000, and a dielectric loss tangent (tan δ) of about 0.14 at room temperature. The substantial dielectric constant suggests that these capacitors are capable of operating effectively at high temperatures. Furthermore, at a frequency of 100 Hz, capacitance values rise with increasing annealing temperature, reaching approximately 70 µF at 800 °C. These results propose that this material holds significant promise as a candidate for high-temperature multilayer ceramic capacitors.