The performance of various solder ball under high shear speed test

This study was aimed to realize the influences of microstructure and shear speed on the fracture behavior of solder ball. The shear behavior of Sn-37Pb, Sn-0.3Ag-0.7Cu, Sn-1Ag-0.5Cu, Sn-3Ag-0.5Cu and Sn-3Ag-0.5Cu-0.06Ni-0.01Ge in solder joint on ball grid array substrate was investigated with differently high shear speed from 10 mm/sec to 1000 mm/sec. The shear speed was found to have strong effect on the fracture feature for all shear tests. In lower shear speed, the mixed failure modes were observed, while the brittle solder/pad interface fracture feature was more pronounced with increasing shear speed. The lead-free solder joints showed a more brittle-look fracture surface than the tin-lead solder joints. The shear strength of joint using Sn-Pb ball was increased with increasing shear speed. The trends of shear strength with applied shear speed for SAC-based solders are uncertain. Conversely, the shear strength of joint using the SAC0307 lead-free ball showed a reverse correlation between the shear speed and shear strength when compared to the Sn-Pb solder joint. The lead-free solder revealed lower shear strength due to the abundant intermetallic compounds formed in the solder ball. The alloy composition added influenced on shear strength under high shear speed condition.