Prediction enhancement of the J-lead interconnection reliability of land grid array sockets

Abstract

The solder joint is a key component in land grid array (LGA) sockets. A simplified solder joint has been widely used in finite element model (FEM) computations because the J-lead interconnection solder joint is relatively complex. Therefore, there are discrepancies between the physical phenomenon and FEM simulations. In this study, an alternative method to simulate the J-lead interconnection solder joint through an interface program using surface evolver software is presented. Simulations of the J-lead interconnection solder joint were improved to reduce the mismatch between the actual physical shape and the simplified finite element models that are typically used to predict component reliability. To perform these simulations, an interface program capable of simulating solder interconnections for twelve different pad–solder combinations was developed. Predictions of J-lead interconnection solder joints were carried out using the interface program. Geometric comparisons between experimental data and predictions showed good agreement, with the exception of wetting height. To evaluate the prediction accuracy of the simulated J-lead solder joints, FEM analysis was performed for the static load and the thermal cycle.