Evaluation Method for Functioning Life of Gold-aluminum Bonding

Gold-aluminum bonding is widely used in connection between silicon chip and substrate of monolithic ICs and multi-chip modules. As a heterogeneous bonding process, intermetallic compounds are inevitably generated at the interface, which will degrade the reliability of Au-Al bonding. In this paper a novel evaluation method for functioning life of Au-Al bonding is proposed. Based on the Arrhenius model and Weibull model, the destructive pulling force of Au-Al bonding is taken as the evaluation parameter, which is easy to be tested, can be directly viewed and has high precision. The functioning life of Au-Al bonding is 22.0 years at 25 ℃ and 9.1 years at 80 ℃. The evaluation method can provide a numerical foundation for usage of Au-Al bonding in various products and a technique reference for reliability evaluation of various heterogenous bonding systems.