Journal of Materials Science: Materials in Electronics

, Volume 29, Issue 17, pp 15233–15240 | Cite as

The interfacial bilayer Cu6Sn5 formed in a Sn–Ag–Cu flip-chip solder joint incorporating Au/Pd metallization during solid-state aging

  • Chien-Lung LiangEmail author
  • Kwang-Lung Lin
  • Po-Jen Cheng


A solid-state reaction between the Sn–Ag–Cu solder and Ni metallization resulted in the formation of interfacial bilayer Cu6Sn5-based intermetallic compounds (IMCs) in a solder joint incorporating Au/Pd metallization. The layer near the Ni metallization was identified as (Cu,Ni,Au)6Sn5 containing 20.3 at.% of Ni and 1.7 at.% of Au, and the layer near the solder matrix was identified as (Cu,Au,Ni,Pd)6Sn5 containing 5.7 at.% of Au, 1.2 at.% of Ni, and 1.0 at.% of Pd. The electron diffraction analysis with high resolution transmission electron microscopy further characterized the interfacial bilayer IMCs as having the same hexagonal crystal structure with different crystal orientations. The kinetics study revealed that the (Cu,Ni,Au)6Sn5 in the interfacial bilayer reaction products was formed during the initial reflow process, while the (Cu,Au,Ni,Pd)6Sn5 layer was formed during subsequent solid-state aging. Predominant growth of the (Cu,Au,Ni,Pd)6Sn5 layer was observed during solid-state aging. In contrast, the growth of the initially formed (Cu,Ni,Au)6Sn5 layer was suppressed. The growth of the (Cu,Au,Ni,Pd)6Sn5 layer was governed by the dissolution of the (Au,Pd)Sn4 IMC that occurred during solid-state aging. The complete dissolution of (Au,Pd)Sn4 resulted in a reactant-limited chemical reaction from the conversion of (Au,Pd)Sn4 to (Cu,Au,Ni,Pd)6Sn5. The development of the interfacial bilayer IMCs in the solder joint incorporating Au/Pd metallization suppressed excessive IMC growth and unfavorable phase transformation during long-term solid-state aging. The detailed mechanism of the formation of the interfacial bilayer Cu6Sn5-based IMCs was investigated in this paper.



The authors acknowledge the financial support of the Ministry of Science and Technology of the Republic of China under MOST104-2221-E-006-028-MY3. We also wish to express our deep appreciation to the ASE group, Kaohsiung for supplying the specimens and for technical support.


  1. 1.
    K.N. Tu, Microelectron. Reliab. 51, 517 (2011)CrossRefGoogle Scholar
  2. 2.
    H. Huebner, S. Penka, B. Barchmann, M. Eigner, W. Gruber, M. Nobis, S. Janka, G. Kristen, M. Schneegans, Microelectron. Eng. 83, 2155 (2006)CrossRefGoogle Scholar
  3. 3.
    C.L. Liang, K.L. Lin, J.W. Peng, J. Electron. Mater. 45, 51 (2016)CrossRefGoogle Scholar
  4. 4.
    C.W. Chen, T.C. Chiu, Y.T. Chiu, C.W. Lee, K.L. Lin, Intermetallics 85, 117 (2017)CrossRefGoogle Scholar
  5. 5.
    Y.C. Chan, D. Yang, Prog. Mater. Sci. 55, 428 (2010)CrossRefGoogle Scholar
  6. 6.
    K.N. Tu, A.M. Gusak, M. Li, J. Appl. Phys. 93, 1335 (2003)CrossRefGoogle Scholar
  7. 7.
    Y. Tang, S.M. Luo, W.F. Huang, Y.C. Pan, G.Y. Li, J. Alloy. Compd. 719, 365 (2017)CrossRefGoogle Scholar
  8. 8.
    Y. Tang, G.Y. Li, Y.C. Pan, J. Alloy. Compd. 554, 195 (2013)CrossRefGoogle Scholar
  9. 9.
    Y. Tang, G.Y. Li, D.Q. Chen, Y.C. Pan, J. Mater. Sci. Mater. Electron. 25, 981 (2014)CrossRefGoogle Scholar
  10. 10.
    Y. Tang, S.M. Luo, K.Q. Wang, G.Y. Li, J. Alloy. Compd. 684, 299 (2016)CrossRefGoogle Scholar
  11. 11.
    T. Laurila, V. Vuorinen, J.K. Kivilahti, Mater. Sci. Eng. R 49, 1 (2005)CrossRefGoogle Scholar
  12. 12.
    W.T. Chen, C.E. Ho, C.R. Kao, J. Mater. Res. 17, 263 (2002)CrossRefGoogle Scholar
  13. 13.
    C.E. Ho, R.Y. Tsai, Y.L. Lin, C.R. Kao, J. Electron. Mater. 31, 584 (2002)CrossRefGoogle Scholar
  14. 14.
    T.L. Shao, T.S. Chen, Y.M. Huang, C. Chen, J. Mater. Res. 19, 3654 (2004)CrossRefGoogle Scholar
  15. 15.
    C.E. Ho, Y.W. Lin, S.C. Yang, C.R. Kao, D.S. Jiang, J. Electron. Mater. 35, 1017 (2006)CrossRefGoogle Scholar
  16. 16.
    J.W. Yoon, B.I. Noh, S.B. Jung, J. Electron. Mater. 40, 1950 (2011)CrossRefGoogle Scholar
  17. 17.
    T. Laurila, V. Vuorinen, M. Paulasto-Kröckel, Mater. Sci. Eng. R 68, 1 (2010)CrossRefGoogle Scholar
  18. 18.
    S.W. Fu, C.Y. Yu, T.K. Lee, K.C. Liu, J.G. Duh, Mater. Lett. 80, 103 (2012)CrossRefGoogle Scholar
  19. 19.
    C.Y. Yu, T.K. Lee, M. Tsai, T.C. Liu, J.G. Duh, J. Electron. Mater. 39, 2544 (2010)CrossRefGoogle Scholar
  20. 20.
    I.T. Wang, J.G. Duh, C.Y. Cheng, J. Wang, Mater. Sci. Eng. B 177, 278 (2012)CrossRefGoogle Scholar
  21. 21.
    C.E. Ho, W.H. Wu, L.H. Hsu, C.S. Lin, J. Electron. Mater. 41, 11 (2012)CrossRefGoogle Scholar
  22. 22.
    C.L. Liang, K.L. Lin, P.J. Cheng, Surf. Coat. Technol. 319, 55 (2017)CrossRefGoogle Scholar
  23. 23.
    C.L. Liang, K.L. Lin, P.J. Cheng, J. Mater. Sci. 52, 11659 (2017)CrossRefGoogle Scholar
  24. 24.
    H.K. Kim, K.N. Tu, P.A. Totta, Appl. Phys. Lett. 68, 2204 (1996)CrossRefGoogle Scholar
  25. 25.
    A.M. Minor, J.W. Morris Jr., Metall. Mater. Trans. A 31A, 798 (2000)CrossRefGoogle Scholar
  26. 26.
    C.E. Ho, R. Zheng, G.L. Luo, A.H. Lin, C.R. Kao, J. Electron. Mater. 29, 1175 (2000)CrossRefGoogle Scholar
  27. 27.
    J.H. Lee, J.H. Park, D.H. Shin, Y.H. Lee, Y.S. Kim, J. Electron. Mater. 30, 1138 (2001)CrossRefGoogle Scholar
  28. 28.
    T. Laurila, V. Vuorinen, T. Mattila, J.K. Kivilahti, J. Electron. Mater. 34, 103 (2005)CrossRefGoogle Scholar
  29. 29.
    M.O. Alam, Y.C. Chan, Chem. Mater. 17, 927 (2005)CrossRefGoogle Scholar
  30. 30.
    C.E. Ho, L.C. Shiau, C.R. Kao, J. Electron. Mater. 31, 1264 (2002)CrossRefGoogle Scholar
  31. 31.
    K. Nogita, T. Nishimura, Scr. Mater. 59, 191 (2008)CrossRefGoogle Scholar
  32. 32.
    G. Zeng, S.D. McDonald, Q.F. Gu, S. Suenaga, Y. Zhang, J.H. Chen, K. Nogita, Intermetallics 43, 85 (2013)CrossRefGoogle Scholar
  33. 33.
    U. Schwingenschlögl, C.D. Paola, K. Nogita, C.M. Gourlay, Appl. Phys. Lett. 96, 061908 (2010)CrossRefGoogle Scholar
  34. 34.
    K. Nogita, C.M. Gourlay, S.D. McDonald, Y.Q. Wu, J. Read, Q.F. Gu, Scr. Mater. 65, 922 (2011)CrossRefGoogle Scholar
  35. 35.
    Y.D. Jeon, S. Nieland, A. Ostmann, H. Reichl, K.W. Paik, J. Electron. Mater. 32, 548 (2003)CrossRefGoogle Scholar
  36. 36.
    Y.D. Jeon, K.W. Paik, A. Ostmann, H. Reichl, J. Electron. Mater. 34, 80 (2005)CrossRefGoogle Scholar
  37. 37.
    L.Y. Hsiao, G.Y. Jang, K.J. Wang, J.G. Duh, J. Electron. Mater. 36, 1476 (2007)CrossRefGoogle Scholar
  38. 38.
    C. Yu, J.Y. Liu, H. Lu, P.L. Li, J.M. Chen, Intermetallics 15, 1471 (2007)CrossRefGoogle Scholar

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© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Department of Materials Science and EngineeringNational Cheng Kung UniversityTainanTaiwan, ROC
  2. 2.Advanced Semiconductor Engineering (ASE) GroupKaohsiungTaiwan, ROC

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