Simultaneous enhancement of dielectric properties and temperature stability in BaTiO3-based ceramics enabling X8R multilayer ceramic capacitor

Modified BaTiO 3 ceramics that possess high dielectric permittivity and acceptable temperature stability have been widely utilized as multilayer ceramic capacitors (MLCCs) for high-frequency bypass and power filtering in automotive applications. However, since the increasing demand for high-capacity and small-size, high-permittivity materials that can serve as dielectric layers in MLCCs are urgently required. In this work, we design and fabricate a special BaTiO 3 -0.03Mg-0.02Y-0.02CaZrO 3 ceramic with a high dielectric permittivity of 3000 and the dielectric variation below ±13% in the temperature range of -55–150°C, fulfilling the requirements of X8R capacitors. To achieve these results, we employed grain size engineering and cation doping, using BaTiO 3 precursors with a particle size of 240 nm to prepare the BaTiO 3 -based ceramics with fine grains, while Mg and Y co-doping was used for improving the temperature stability due to dielectric dispersion. Utilizing these high-permittivity BaTiO 3 -based materials, we fabricated MLCCs that satisfy the X8R criterion, possessing a high dielectric constant of 2950 and a high breakdown field (410 kV/cm).