Solder Joint Reliability of SnAgCu Solder Refinished Components Under Temperature Cycling Test

SnAgCu (SAC) solder is being offered as a lead-free termination finish. SAC finish is obtained by dipping the terminals of components into molten SAC solder. However, the reliability of solder joints formed with SAC solder refinished components needs to be determined in order to evaluate the effects of the SAC solder refinishing process. In this paper, the strength of solder joints with SAC solder refinished thin small outline packages (TSOPs) was evaluated by the shear test. The reliability of solder joints formed with SAC solder refinished components, including TSOPs and resistors, was evaluated by a temperature cycling test. Original Sn finished components were used as a baseline for comparison. It was found that SAC solder refinishing increased solder joint strength. SAC solder refinishing decreased the fatigue life of solder joints of TSOPs and increased the fatigue life of resistors under temperature cycling conditions.