|About this Abstract
||2017 TMS Annual Meeting & Exhibition
||Emerging Interconnect and Pb-free Materials for Advanced Packaging Technology
||Study of Electromigration Mechanism in Pb-free Tricrystals Ball Grid Array Solder Joints
||Yu Tian, Jing Han, Fu Guo
|On-Site Speaker (Planned)
The EM mechanism of SAC305 solder joints was closely related to Sn-grain orientation, especially in tricrystals BGA solder joints. A BGA specimen of Sn-3.0Ag-0.5Cu (SAC305) solder with cross-sectioned edge row was subjected to 2.1×103A/cm2 at room temperature for 600 hours. The results showed that the growth mechanism of Cu6Sn5 IMCs had a close relationship with the c axis three-dimensional direction of Sn grain. When the direction of c axis in Sn grain was nearly parallel to the direction of current, the Cu6Sn5 IMCs grew rapidly and stacked at the tricrystals grain boundary. That was because the diffusion rate of Cu atoms was fast along the direction of c axis, and the high interfacial energy at the grain boundary. Futhermore, based on lower resistivity of c axis, the Cu6Sn5 IMCs preferred to internal growth when the c axis of Sn grain along the cross section inwards.
||Planned: Supplemental Proceedings volume