Wirebonding Reliability Techniques and Analysis

A method for wirebond evaluation is presented which allows for rapid conclusions concerning the quality of wirebonds produced by a given process. It uses the whole spectrum of wirebond strengths produced by that process to arrive at a decision rather than using only information from the few weakest bonds. A quantitative failure rate can easily be assigned to the wirebonds from a given process based on statistical data. The situation where more than one failure mechanism is present in a process is discussed. Case histories are presented using the proposed method for wirebond process evaluation. Information concerning process activation energies as well as some recommendations for improving wirebonding quality are also presented.