Electromigration Reliability and Morphologies of 62Sn–36Pb–2Ni and 62Sn–36Pb–2Cu Flip-Chip Solder Joints

Failure Mechanism of Sn-Ag-Cu Flip-chip Solder Joints with Different Cu Weight Contents Under Comparatively Low Current Stressing

“…This trend coincides those reported by Lai et al [7,8], namely, solder joints with a greater Cu weight content turn out to have a longer electromigration life under comparatively low current stressing. Nevertheless, these studies also showed that under comparatively high current stressing, the superiority of a greater Cu weight content is taken over, as was also figured out by Shao According to the electrothermal coupling analysis [7,10,11], for the particular flip-chip test vehicle subjected to this specific test condition, the temperature difference over a single solder joint does not exceed 1C, which corresponds to a temperature gradient less than 100°C/cm, taking the standoff of the solder joint as the reference length.…”

“…In addition, by comparing electromigration reliability corresponding to different Sn-Ag-Cu solder joints, Lai et al [7] figured out that as the Cu weight content of the solder composition increases, the fatigue life increases under the test condition of 5 kA/cm2 at 150°C but decreases under that of 20 kA/cm2 at 30°C. A similar trend has also been reported for 62Sn-36Pb-2Ni and 62Sn-36Pb-2Cu solder joints under these two test conditions [8]. Table 1 kA/cm2 and an ambient temperature at 1500C, electromigration reliability and patterns of Sn-3Ag-0.5Cu and Sn-3Ag-1.5Cu/Sn-3Ag-0.5Cu composite flip-chip solder joints with Ti/Ni(V)/Cu UBM are compared.…”

Failure mechanisms of solder interconnects under current stressing in advanced electronic packages

“…However, the reason for such a log-normal distribution has not been clarified. On the other hand, a Weibull analysis has been performed on time-to-failure (TTF) data in other research studies [6,45]. In our case, the EM failure of Sn3.5Ag1.0Cu solder joints followed Weibull statistics very well with current densities ranging from 1 Â 10 4 to 2 Â 10 4 A/cm 2 at 100, 125, and 150°C [19].…”

Electromigration Reliability and Morphologies of Cu Pillar Flip-Chip Solder Joints with Cu Substrate Pad Metallization

“…Individual electrical resistances on the three sections labeled R 1 , R 2 , and R 3 were monitored in situ, and the experiments were terminated once the resistance of each of these three sections exceeded 2 X. [5][6][7]15,16 Our experience shows that this failure criterion refers to the open-circuit failure rather than the failure corresponding to partial defects in the solder joint system, formed during current stressing.…”