Electromigration-induced morphology and microstructure changes in Sn58Bi/Sn3.0Ag0.5Cu compositional solder interconnect

The paper aims to understand the line-type solder joints electromigration phenomenon in the compositional solder joint system. The current density of 1.0×10
⁴
A/cm
²
at room temperature was researched. The two kinds of solder joints changed their morphology at both anode sides and cathode sides after current stressing. For structure compositional solder joint, Bi layers formed in the anode side, which indicated that Bi was the major diffusion element from cathode to anode. Furthermore, through the comparison of the two kinds of solder joints, Bi layers didn't form at the anode in composition compositional solder joint, it was easy to find that Ag3Sn suppressed the migration of atomic Bi during electromigration. Also, the Cu-Sn IMCs growth behavior at the cathode and anode were observed when the current passed through the two kinds of samples.