Skip to main content
Log in

Effect of Ge addition on wettability, copper dissolution, microstructural and mechanical behavior of SnCu–Ge solder alloy

  • Published:
Journal of Materials Science: Materials in Electronics Aims and scope Submit manuscript

Abstract

This paper explores the effects of Germanium (Ge) addition on the wetting behavior, copper dissolution, IMC formation, microstructure and mechanical behavior of SnCu alloy. Static copper dissolution was conducted as a function of contact time and in the temperature range of 260–300 °C. The results show that the Ge doped alloy has the lowest copper dissolution rate compared to SnCu, SAC305, and very much comparable with SnPb solder thus making it suitable alloy for the wave soldering process. Two solderability standards measurement (JIS vs. IPC) have been executed on different surface finishes such as OSP, ENIG, ImAg commonly used in industrial soldering process. The results showed that addition of Ge significantly improves the wetting/spread performance for all the surface finishes (ENIG, OSP and ImAg). Contact angles range from 17°–30°, the lowest contact angles being observed on ENIG surface. Microstructural analysis showed Ge addition refine the grain structure of SnCu–0.01Ge alloy. A thin IMC layer was observed, and IMC growth was not significant after multiple reflows as compared to Sn–Cu alloy. Similarly, Ge addition increases the hardness value due to uniform microstructure of SnCu–Ge alloy. The tensile testing results also showed an increase in tensile strength and tolerable ductility.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10
Fig. 11
Fig. 12
Fig. 13
Fig. 14
Fig. 15
Fig. 16
Fig. 17
Fig. 18
Fig. 19
Fig. 20

Similar content being viewed by others

References

  1. M. Abtew, G. Selvaduray, Lead free solders in microelectronics. Mater. Sci. Eng. R 27, 95–141 (2000)

    Article  Google Scholar 

  2. J.W. Evans, A Guide to Lead-Free Solders: Physical Metallurgy and Reliability, Springer, New York, 2007

    Google Scholar 

  3. H.Z. Huang, X.Q. Wei, D.Q. Tan, L. Zhou, Effects of phosphorus addition on the properties of Sn–9Zn lead free solder alloy. Int. J. Miner. Metall. Mater. 6, 563–567 (2013)

    Article  Google Scholar 

  4. A. Xian, G.L. Gong, Oxidation behavior of molten tin doped with phosphorus. J. Electron. Mater. 12, 1669–1678 (2007)

    Article  Google Scholar 

  5. K.M. Watling, A. Chandler-Temple, K. Nogita, XPS analysis of oxide films on lead free solders with trace additions of germanium and gallium. Mater. Sci. Forum 857, 63–67 (2016)

    Article  Google Scholar 

  6. X. Yan, K. Xu, J. Wang, X. Wei, W. Wang, Effect of P and Ge doping on microstructure of Sn-0.3 Ag-0.7 Cu/Ni–P solder joints, Soldering Surf. Mount Technol. 28, 215–221 (2016)

    Article  Google Scholar 

  7. E.P. Leng, W.T. Ling, N. Amin, I. Ahmad, T.Y. Han, C.W. Chiao, A.S.M.A. Haseeb, BGA lead free C5 solder system improvement by Germanium addition to Sn3.5Ag and Sn-3.8 Ag-0.7 Cu solder alloy. in Electronics Packaging Technology Conference, pp. 82–91, 2009

  8. M.G. Cho, S.K. Seo, H.M. Lee, Undercooling, microstructures and hardness of Sn-rich Pb-free solders on Cu-xZn alloy under bump metallurgies. Mater. Trans. 50, 2291–2296 (2009)

    Article  Google Scholar 

  9. A. Sharif, Y.C. Chan, Dissolution kinetics of BGA Sn–Pb and Sn–Ag solders with Cu substrates during reflow. Mater. Sci. Eng. B 106, 126–131 (2004)

    Article  Google Scholar 

  10. F. Byle, D. Jean, D. Lee, A study of copper dissolution in Pb-Free solder fountain systems, in Proceedings of SMTA International, 2006

  11. D. Maio, C.P. Hunt, On the factors affecting the dissolution of copper in molten lead free solders and development of a method to assess the soldering parameters. Soldering Surf. Mount Technol. 21, 24–31 (2009)

    Article  Google Scholar 

  12. J.F. Li, S.H. Mannan, M.P. Clode, D.C. Whalley, D.A. Hutt, Interfacial reactions between molten Sn–Bi–X solders and Cu substrates for liquid solder interconnects. Acta Mater. 54, 2907–2922 (2006)

    Article  Google Scholar 

  13. G. Humpston, D.M. Jacobson, Solder spread: a criterion for evaluation of soldering. Gold Bull. 3, 83–96 (1990)

    Article  Google Scholar 

  14. P.T. Vianco, An overview of surface finishes and their role in printed circuit board solderability and solder joint performance. Circ. World 25, 6–24 (1999)

    Article  Google Scholar 

  15. M.F. Arenas, V.L. Acoff, Contact angle measurements of Sn–Ag and Sn–Cu lead free solders on copper substrates. J. Electron. Mater. 12, 1452–1458 (2004)

    Article  Google Scholar 

  16. S.H. Wang, T.S. Chin, C.F. Yang, S.W. Chen, C.T. Chuang, Pb-free solder alloy based on Sn–Zn–Bi with the addition of germanium. J. Alloys Compd. 497, 428–431 (2010)

    Article  Google Scholar 

  17. R.J.K. Wassink, Soldering in Electronics: A Comprehensive Treatise on Soldering Technology for Surface Mounting and Through Hole Techniques, Electrochemical Publications, Scotland, 1994

    Google Scholar 

  18. R.W. Hertzberg, Deformation and Fracture Mechanics of Engineering Materials, 4th edn. Wiley, New York, 1996

    Google Scholar 

  19. F. Lang, H. Tanaka, O. Munegata, T. Taguchi, T. Narita, The effect of strain rate and temperature on the tensile properties of Sn–3.5 Ag solder. Mater. Charact. 54(3), 223–229 (2005)

    Article  Google Scholar 

Download references

Acknowledgements

This research was supported by Kester R & D, material science division. The authors thankful to ITW Tech Center and Buehler for sample preparation and analysis.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to M. Hasnine.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Hasnine, M., Tolla, B. & Karasawa, M. Effect of Ge addition on wettability, copper dissolution, microstructural and mechanical behavior of SnCu–Ge solder alloy. J Mater Sci: Mater Electron 28, 16106–16119 (2017). https://doi.org/10.1007/s10854-017-7511-4

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s10854-017-7511-4

Navigation