A new design-for-reliability approach to thermal fatigue life prediction of leadless solder joints

Summary form only given. While a tremendous amount of work has been done in leadless solder joint reliability, the detailed thermal fatigue failure mechanisms and their relations with key parameters, e.g., solder fillet, inner end geometry, and microstructure, have, however, not yet been fully understood. Also life prediction methodologies that account for the physics of failure still remain to be developed. In this paper the failure mechanisms of 2512 LCR solder joints are discussed based on thermal fatigue test results, and reliability models for fatigue crack initiation and propagation and the effect of solder height are elaborated.