Mechanism of electrical stress‐induced failure in multilayer ceramic capacitors: Experimental and simulation approaches

Abstract Multilayer ceramic capacitors (MLCCs) face the threat of failure due to various electrical stresses during long‐term use. This study systematically investigates the mechanisms of breakdown failure in MLCCs under impulse voltage, ramped voltage, and endurance voltage, using a combination of experimental characterization and finite element method simulations. The distributions of the electric field, mechanical stress field, and thermal effects within MLCCs were comprehensively analyzed. As the duration of voltage application increases, the breakdown voltage of MLCCs decreases. All electrical stress‐induced failures occur at the edge regions with inferior electrode quality, where severe localized electric field concentration is present. The failure mechanism induced by short‐duration, high‐voltage impulse stress is electromechanical breakdown, which tends to occur at the L‐direction edges where mechanical stress is more concentrated. In contrast, the failure mechanisms induced by longer‐duration, lower‐voltage ramped voltage and endurance voltage are electrothermal breakdown, preferentially initiating at the W‐direction edges, where heat accumulation is more pronounced due to poorer thermal dissipation. The findings of this study provide a theoretical reference for a deeper understanding of the failure behavior of MLCCs under electrical stress and for improving their electrical reliability.