About this Abstract |
Meeting |
2021 TMS Annual Meeting & Exhibition
|
Symposium
|
Electronic Packaging and Interconnections 2021
|
Presentation Title |
Microalloying Effects on Intermetallic Compound Growth and Mechanical Reliability of Sn-Bi Solder Joints |
Author(s) |
Yaohui Fan, Yifan Wu, Travis F. Dale, Sukshitha Achar, Hannah N. Fowler, Nilesh U. Badwe, Raiyo F. Aspandiar, John E. Blendell, Ganesh Subbarayan, Carol A. Handwerker |
On-Site Speaker (Planned) |
Yaohui Fan |
Abstract Scope |
Low temperature interconnect technologies based on Sn-Bi alloys are being considered for substituting Sn-Ag-Cu (SAC) solders to form joints with significantly lower melting temperatures than homogeneous SAC joints. Microstructure development studies of reflow and aging are important in understanding the relationship between alloy composition and mechanical reliability, failures paths, particularly in comparison with SAC alloys. This study focused on intermetallic growth between several SnBi eutectic and off-eutectic alloys with different microalloying elements (Ag, Sb, Cu) soldered on electroless nickel immersion gold (ENIG) metallization. In this study, Au from the ENIG finish catalyzed rapid (Au,Ni)Sn4 intermetallic growth at solder-Ni interface in SnBi and SnBiAg homogeneous joints during solid-state annealing. Formation of (Au,Ni)Sn4 led to significant embrittlement of the interconnects during mechanical loading. Further study found that the growth rate of (Au,Ni)Sn4 intermetallic could be reduced by Ag and Sb alloying of SnBi solders, and could be totally eliminated with Cu addition. |
Proceedings Inclusion? |
Planned: |
Keywords |
Electronic Materials, Mechanical Properties, Joining |