Dielectric and ferroelectric property changes of BaTiO3 ceramics under in-plane stress application

초록

Layered ceramic components with metallic internal electrodes, such as multilayer ceramic capacitors (MLCCs), exhibit internal residual stresses induced during the cooling step of the sintering process. These stresses have a significant impact on the final properties of the ceramic components. However, while a few important scientific results have been reported to date, these studies have primarily interpreted the impact of stress on the electrical properties of ceramics from a singular perspective. Understanding and analyzing stress effects in ferroelectric ceramics are crucial for enhancing reliability and life time while assessing electrical property changes relative to single-layer materials. In this study, finite element analysis (FEA) is used to estimate the internal residual stress levels between ferroelectric BaTiO3 ceramic and electrode layers in the MLCCs structure. The simulation results guide the application of comparable levels of in-plane compressive stress to ferroelectric BaTiO3 ceramics, enabling characterization of their dielectric and ferroelectric properties. At low in-plane compressive stress, non180 degrees domain switching and phase transitions enhance dielectric constant and ferroelectric properties, however exceeding the critical threshold value leads to domain clamping and reduced electrical properties. This study confirms that application of in-plane stress influences both domain structure and crystal structure changes in BaTiO3 ceramics and provides critical insights for improving the performance and reliability of ferroelectric devices.

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