Thermal Fitigure Life Prediction on PBGA Solder Joints of Typical Pad Finish/Solder Combination

The degradation characteristics and life prediction of the typical PCB Pad/solder pastes combinations including the ENIG PCB pad /lead-free BGA SAC305 ball with lead-free process, the Sn-HASL PCB pad/lead-free BGA SAC305 ball with backward compatible mixing process and the Sn-HASL PCB pad/lead-tin BGA 63SnPb ball with lead-tin process were investigated and compared based on the accelerated life experiments. The data of thermal cycle to failure was processed and it was confirmed that the thermal cycle to failure of the investigated three type solder joints all could be fitted by Weibull distribution law.