Resistance Changes in Eutectic Sn-Bi Solder Joints 
During Electromigration
The resistance of electronic interconnects made with Sn-based solders experiences significant deterioration during service in high-performance electronic products. During electromigration damage, metal atoms/ions can migrate in the direction of electron flow. Accordingly, accumulation of metal atoms/ions at the anode interface can induce surface bulging. On the other hand, depletion of metal atoms/ions at the cathode interface can induce surface dimpling. In addition, the different α-rich and β-rich phases in a binary eutectic system were found to separate in the bulk region of eutectic Sn-Bi solder joints. Such atomic movement leads to complex interactions between the resistance changes of electronic solder joints during the different stages of electromigration. In order to clarify such scenarios, a LabVIEW®-controlled system was employed to quantitatively measure the instantaneous resistance values after an electric current was applied. This study investigated the effects of a high current density (104 A/cm2) at two different ambient temperatures (25°C and 80°C) on the deterioration of resistance changes during the early stage of the electromigration process.