Reliability of wirebonds in micro-electronic packages

Abstract

Purpose ¿ At present, over 95 percent of the manufactured packages are still being wire bonded. Owing to the ongoing trend of miniaturization, material changes, and cost reduction, wire bond-related failures are becoming increasingly important. This paper aims to understand these kinds of failures.

Design/methodology/approach ¿ Different finite element (FE) techniques are explored to their ability to describe the thermo-mechanical behavior of the wire embedded in the electronic package. The developed nonlinear and parametric FE models are able to predict the strong nonlinear behavior of wire failures and multi-failure mode interaction accurately and efficiently.

Findings ¿ It is found that both processing and testing environments as well as the occurrence of delamination strongly increase the risk for wire failures. The results indicate that processing and testing influences are much less than those of the delamination.

Practical implications ¿ Package designers should focus on limiting the occurrence of delamination around wire bond and/or stitch areas.

Originality/value ¿ Combining the strengths of predictive modeling with simulation-based optimization methods, the optimal wire shape is obtained.