Influence of thickness and number of dielectric layers on residual stresses in micromultilayer ceramic capacitors

Abstract

The residual stresses due to high-temperature processing in micromultilayer ceramic capacitors (MLCCs) with various thicknesses and numbers of dielectric ceramic layers were investigated by using a three-dimensional elastoplastic finite element model with temperature-dependent material properties taken into account. For comparison, an explicit analytical solution for the in-plane residual stress in the dielectric ceramic layer was derived. Both the numerical results and the analytical model showed that the thickness ratio of the dielectric layer to electrode layer has a dominant impact on the residual stress states. There exists a critical thickness for the dielectric ceramic layer in MLCCs in the case of a given thickness of the electrode layer, below which both high tensile out-of-plane stresses and high compressive in-plane stresses could cause the cracking of the brittle dielectric layers near the electrode tips and/or the debonding of the electrode/dielectric interface.