About this Abstract |
| Meeting |
2026 TMS Annual Meeting & Exhibition
|
| Symposium
|
Electronic Packaging and Interconnection Materials III
|
| Presentation Title |
Zn-Induced Modifications in Intermetallic Formation at the Sn-Bi/Cu Interface |
| Author(s) |
Carolina de Siqueira Simioli, Guilherme Lisboa de Gouveia, Jose Spinelli |
| On-Site Speaker (Planned) |
Jose Spinelli |
| Abstract Scope |
The reliability of solder joints in microelectronic devices depends on the interfacial reaction between the solder alloy and the copper substrate. Sn-Bi alloys are promising candidates due to their low cost, good mechanical performance, and environmental compliance. However, the formation of the Cu₆Sn₅ IMC during service can degrade mechanical integrity. This study evaluates Sn-40wt.%Bi alloys with 0, 2, and 10%Zn additions, soldered in Cu substrates and subjected to isothermal heat treatment at 120°C for 120, 240, and 360h. Optical microscopy and SEM-EDS analyses were used to characterize interfacial morphological and compositional changes. The wetting angle of solder droplets on Cu was also measured. The results reveal a direct influence of Zn addition, including the formation of a Cu-Zn compound layer, enhanced Zn diffusion into the substrate, increased wetting angle, and retarded Cu₆Sn₅ growth. These findings provide new insights into interfacial evolution and improved reliability of Sn-Bi-based solder joints. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Phase Transformations, Process Technology, |