Finite-Element Analysis of Ceramic Multilayer Capacitors: Failure Probability Caused by Wave Soldering and Bending Loads


  • A. Jagota—contributing editor

  • Supported by the Deutsche Forschungsgemeinschaft (German Research Society), Bonn, Germany.


A two-dimensional numerical model that predicts the reliability of multilayer capacitors (MLCs) during soldering and bending is presented. The Weibull parameters used in the model are based on measurements of soldered MLC devices. The preheating and soldering temperatures have a dominant impact on the failure probability, in comparison to the thickness of the nickel layer, the soft solder geometry, and the number of inner electrodes. Comparison of calculated and measured reliability of three MLC sizes leads to the assumption that residual stresses due to the manufacturing process or size-related microstructure are important.