| About this Abstract |
| Meeting |
2010 TMS Annual Meeting & Exhibition
|
| Symposium
|
Pb-Free Solders and Emerging Interconnect and Packaging Technologies
|
| Presentation Title |
Nucleation and Solidification of Sn in Pb Free, SnAgCu Solder Joints |
| Author(s) |
Babak Arfaei, Yan Xing, Eric Cotts |
| On-Site Speaker (Planned) |
Babak Arfaei |
| Abstract Scope |
The replacement of eutectic Pb-Sn with near eutectic Sn-Ag-Cu to create Pb free solder joints has provided a number of challenges. Ag and Cu are much less effective than Pb in promoting solidification of Sn, so pronounced undercooling, and thus rapid solidification effects on solder joint microstructure are observed in standard procedures. Furthermore, six-fold, cyclic growth twinning of Sn during solidification from the melt is generally observed in Sn-Ag-Cu solders. This study examines variations in solder joint microstructure resulting from changes in solidification pathways. The solder impurity content, sample size and solder joint properties, such as substrate metallization, are varied. Both variation of nucleation rates of Sn from the Sn-Ag-Cu melt, and of resultant Sn grain solidification morphologies, are reported. Studies of the failure of Sn-Ag-Cu solder joints are discussed in the context of these different Sn grain morphologies. |
| Proceedings Inclusion? |
Planned: Journal of Electronic Materials |