On wire failures in micro-electronic packages

At present, over 95% of the manufactured packages are still being wire bonded. Due to the ongoing trend of miniaturalization, material changes, and cost reduction, wire bond related failures are becoming increasingly important. Different finite element techniques are explored to their ability to describe the thermomechanical behavior of the wire embedded in the electronic package. The developed nonlinear and parametric finite element models are able to predict the strong nonlinear behavior of wire failures and multi-failure mode interaction accurately and efficiently. It is found that both processing and testing environments as well as the occurrence of delamination strongly increase the risk for wire failures. Our results indicate that processing and testing influences are much less than those of the delamination. Combining the strengths of predictive modeling with simulation-based optimization methods, the optimal wire shape is obtained.