| About this Abstract |
| Meeting |
2024 TMS Annual Meeting & Exhibition
|
| Symposium
|
Electronic Packaging and Interconnection Materials
|
| Presentation Title |
Effect of Sb and Ag Addition on the Melting and Solidification of Near-eutectic Sn-Bi Solder Alloys |
| Author(s) |
Yifan Wu, Hannah Nicole Fowler, Nathaniel Weddington, Sean Yenyu Lai, Sukshitha Achar Puttur Lakshminarayana, Sui Xiong Tay, Aleena Masaeng, John Blendell, Ganesh Subbarayan-Shastri |
| On-Site Speaker (Planned) |
Yifan Wu |
| Abstract Scope |
Low temperature solders based on Sn-Bi are used as substitutes for Sn-Ag-Cu (SAC) alloys, reducing reflow temperature and, hence, warpage-induced defects. Understanding the effects of microalloying elements on solder mechanical, microstructural, and thermodynamic properties is an essential part of alloy design. This study focuses on the changes in melting and solidification behavior of near-eutectic Sn-Bi alloys with Sb (0.5-2wt%) and Ag (0-1wt%) additions, and microstructure evolution and intermetallic compound (IMC) growth during isothermal aging at 85°C. Our DSC studies show that, while Sb increases the alloy melting temperature, it also reduces undercooling. This reduction in undercooling is largest for 2wt% Sb alloys in which large SnSb IMCs serve as nucleating sites for Sn dendrites producing a 4˚C undercooling. We discuss these results in light of the observed changes in mechanical properties with isothermal aging of Sb and Ag-containing alloys in thermal cycling performance of the Sn-Bi alloy solder joints. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Electronic Materials, Phase Transformations, Characterization |