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Intermetallic Reactions in Sn-0.4Co-0.7Cu Solder BGA Packages with an ENIG Surface Finish

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Abstract

As-cast Sn-0.4Co-0.7Cu solder contains both (Cu0.98Co0.02)6Sn5 and (Co0.85Cu0.15) Sn3 intermetallic phases in the matrix. After reflowing, the Au thin film in the electroless Ni/immersion Au (ENIG) surface-finished Sn-0.4Co-0.7Cu solder ball grid array (BGA) packages dissolved rapidly into the solder matrix to form AuSn4 intermetallics, and a thin layer of (Cu0.57Ni0.35Au0.08)6Sn5 intermetallic compound appeared at the solder/pad interface, growing very slowly during aging at 100°C. Increasing the aging temperature to 150°C caused the formation of a new intermetallic layer, (Ni0.79Cu0.21)3Sn4, at the (Cu0.57Ni0.35Au0.08)6Sn5/Ni interface. The reflowed Sn-0.4Co-0.7Cu BGA packages have a ball shear strength of 6.8 N, which decreases to about 5.7 N and 5.5 N after aging at 100°C and 150°C, respectively. The reflowed and aged solder joints fractured across the solder balls with ductile characteristics in ball shear tests.

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References

  1. K. Zeng, K.N. Tu. (2002) Mater. Sci. Eng. R38, 55

    CAS  Google Scholar 

  2. L.B. Liu, C. Andersson, J. Liu, Y.C. Chan, Interpack 2003–35126, Int. Electronic Packaging Technical Conf. Exhib. (New York: ASME, 2003), pp. 141–146

    Google Scholar 

  3. L.B. Liu, C. Andersson, J. Liu. (2004) J. Electron. Mater. 33, 935. doi:10.1007/s11664-004-0019-8

    Article  CAS  Google Scholar 

  4. C. Andersson, P. Sun, and J. Liu, J. Alloys Compd. 457, 97 (2008)

    Google Scholar 

  5. P. Sun, C. Andersson, X. Wei, Z. Cheng, D. Shangguan, J. Liu (2006) Mater. Sci. Eng. B 135, 134. doi:10.1016/j.mseb.2006.08.051

    Article  CAS  Google Scholar 

  6. S.K. Kang, V. Ramachandran. (1980) Scripta Metall. 14, 421. doi:10.1016/0036-9748(80)90338-5

    Article  CAS  Google Scholar 

  7. K.Y. Lee, M. Li. (2001) Metall. Mater. Trans. 32A, 2666. doi:10.1007/s11661-001-0058-1

    Article  CAS  Google Scholar 

  8. M.Y. Chiu, S.Y. Chang, Y.H. Tseng, Y.C. Chan, T.H. Chuang, (2002) Z. Metallkd. 93, 248

    CAS  Google Scholar 

  9. T.H. Chuang, S.Y. Chang, L.C. Tsao, W.P. Weng, H.M. Wu. (2003) J. Electron. Mater. 32, 195. doi:10.1007/s11664-003-0193-0

    Article  CAS  Google Scholar 

  10. J.H. Lau, C.P. Wong, N.C. Lee, R.S.W. Lee, Electronics Manufacturing: With Lead-Free, Halogen-Free, Conductive Adhesive Materials (New York: McGraw-Hill Handbooks, 2003)

    Google Scholar 

  11. T.H. Chuang, S.F. Yen, M.D. Cheng. (2006) J. Electron. Mater. 35, 302. doi:10.1007/BF02692450

    Article  CAS  Google Scholar 

  12. T.H. Chuang, S.F. Yen, H.M. Wu. (2006) J. Electron. Mater. 35, 310. doi:10.1007/BF02692451

    Article  CAS  Google Scholar 

  13. K. Ishida, T. Nishizawa, (1991) J. Phase Equil. 12, 88

    Article  CAS  Google Scholar 

  14. H. Okamato, (1993) J. Phase Equil. 14, 3

    Google Scholar 

  15. U. Gosele, K.N. Tu. (1982) J. Appl. Phys. 53, 3252. doi:10.1063/1.331028

    Article  Google Scholar 

  16. I.E. Anderson, J.C. Foley, B.A. Cook, J. Harringa, R.L. Terpstra, O. Unal. (2001) J. Electron. Mater. 30, 1050. doi:10.1007/s11664-001-0129-5

    Article  CAS  Google Scholar 

Download references

Acknowledgements

This research was financially supported by the National Taiwan University under Grant 95R0210 and by the National Science Council, Taiwan, under Grant NSC96-2221-E002-150-MY3.

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Authors and Affiliations

  1. Institute of Materials Science and Engineering, National Taiwan University, Taipei, 106, Taiwan

    T.H. Chuang, C.C. Jain & H.M. Wu

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  1. T.H. Chuang
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  2. C.C. Jain
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  3. H.M. Wu
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Correspondence to T.H. Chuang.

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Chuang, T., Jain, C. & Wu, H. Intermetallic Reactions in Sn-0.4Co-0.7Cu Solder BGA Packages with an ENIG Surface Finish. J. Electron. Mater. 37, 1734–1741 (2008). https://doi.org/10.1007/s11664-008-0501-9

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  • DOI: https://doi.org/10.1007/s11664-008-0501-9

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