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Experimental investigations in the intermetallic and microvoid formation in sub-200 °C Cu–Sn bonding

  • Harindra Kumar Kannojia
  • Pradeep DixitEmail author
Article
  • 31 Downloads

Abstract

This paper reports the intermetallic growth and microvoid formation in the Cu–Sn layers, which were annealed at low temperatures (sub-200°C) for durations varying from 120 to 1440 min. A 10 µm thick tin was electrodeposited on copper samples. Both Cu6Sn5 and Cu3Sn IMCs were formed and had a non-uniform scalloped shaped profile but with different scallops sizes. Void growth was studied at three different locations, i.e., the Cu–Cu3Sn interface, within the Cu3Sn, and at the Cu3Sn–Cu6Sn5 interface. The void size in these locations increased with increasing annealing durations and temperatures due to the coalescence of nearby voids. The void fraction at the Cu–Cu3Sn and Cu3Sn–Cu6Sn5 interfaces was observed to decrease, whereas the void fraction within the Cu3Sn IMC increased with increasing annealing durations. The largest voids were seen at the Cu–Cu3Sn interface, while the highest void fraction was found within the Cu3Sn IMC. The overall void size and void fractions for all experimental conditions were always smaller than 3 µm2 and 1.44 µm−1, respectively. The obtained results can be used in the hermetic packaging of MEMS devices performed at sub-200 °C. Processing at these low temperatures result in reduced thermo-mechanical stress and also eliminate the molten tin squeezing-out from the bonding zone, which is a known issue in Cu–Sn solid–liquid inter-diffusion bonding performed at temperature > 232 °C.

Notes

Acknowledgements

The authors would like to acknowledge the financial support from Industrial Research and Consultancy Centre (IRCC), IIT Bombay, under the research Grant 15IRCCSG002.

References

  1. 1.
    M.A. Schmidt, Proc. IEEE 86, 8 (1998)CrossRefGoogle Scholar
  2. 2.
    M. Esashi, J. Micromech. Microeng. 18, 7 (2008)CrossRefGoogle Scholar
  3. 3.
    R.R. Tummala, Fundamentals of Microsystems Packaging, 2nd edn. (McGraw-Hill Education, New York, 2001), pp. 580–610Google Scholar
  4. 4.
    S. Farrens, “Metal based wafer level packaging,” in Int. Wafer-Level Pack. Conf. (IWLPC), 2008, pp. 8–14Google Scholar
  5. 5.
    Y. I. Kim, K. H. Yang, and W. S. Ire, in Annual Inter. Rel. Phy. Sym., 2 (2004)Google Scholar
  6. 6.
    K.N. Tu, Acta Mater. 21, 4 (1973)CrossRefGoogle Scholar
  7. 7.
    M. Onishi, H. Fujibuchi, Trans. Japan Inst. Met. 16, 9 (1975)CrossRefGoogle Scholar
  8. 8.
    W. Tang, A. He, Q. Liu, D.G. Ivey, Trans. Nonferrous Met. Soc. China 20, 8 (2010)Google Scholar
  9. 9.
    H. Liu, K. Wang, K.E. Aasmundtveit, N. Hoivik, J. Electron. Mater. 41, 9 (2012)Google Scholar
  10. 10.
    T.T. Luu, A.N.I. Duan, K.E. Aasmundtveit, N. Hoivik, J. Electron. Mater. 42, 12 (2013)CrossRefGoogle Scholar
  11. 11.
    B.S. Lee, S.K. Hyun, J.W. Yoon, J. Mater. Sci.: Mater. Electron. 28, 11 (2017)Google Scholar
  12. 12.
    T. Laurila, V. Vuorinen, J.K. Kivilahti, Mater. Sci. Eng. R Rep. 49, 1–60 (2005)CrossRefGoogle Scholar
  13. 13.
    A. Munding, H. Hubner, A. Kaiser, S. Penka, P. Benkart, E. Kohn, Wafer Level 3-D ICs Process Technology (Springer, New York, 2008), p. 131Google Scholar
  14. 14.
    C. Yuhan, L. Le, J. Semicond. 30, 8 (2009)CrossRefGoogle Scholar
  15. 15.
    B. Balakrisnan, C.C. Chum, M. Li, Z. Chen, T. Cahyadi, J. Electron. Mater. 32, 3 (2003)CrossRefGoogle Scholar
  16. 16.
    H. Liu, G. Salomonsen, K. Wang, K.E. Aasmundtveit, N. Hoivik, IEEE Trans. Componen. Packag. Manuf. Technol. 1, 9 (2011)Google Scholar
  17. 17.
    S. Bader, W. Gust, H. Hieber, Acta Mater. Mater. 43, 1 (1995)CrossRefGoogle Scholar
  18. 18.
    A. Duan, T. Luu, K. Wang, K. Aasmundtveit, N. Hoivik, J. Micromech. Microeng. 25(9), 097001 (2015)CrossRefGoogle Scholar
  19. 19.
    C. Hang, Y. Tian, R. Zhang, J. Mater. Sci.: Mater. Electron. 24, 10 (2013)Google Scholar
  20. 20.
    H.K. Kannojia, S.K. Sharma, P. Dixit, J. Electron. Mater. 47, 12 (2018)CrossRefGoogle Scholar
  21. 21.
    J.F. Li, P.A. Agyakwa, C.M. Johnson, Acta Mater. 59(3), 1198–1211 (2011)CrossRefGoogle Scholar
  22. 22.
    N. Zhao, Y. Zhong, M.L. Huang, H.T. Ma, W. Dong, Sci. Rep. 5, 131491 (2015)Google Scholar
  23. 23.
    G. Ross, V. Vuorinen, M. Paulasto-Kröckel, J. Alloys Compd. 677, 127–138 (2016)CrossRefGoogle Scholar
  24. 24.
    G. Ghosh, M. Asta, J. Mater. Res. 20, 11 (2005)CrossRefGoogle Scholar
  25. 25.
    K. Nogita, C.M. Gourlay, S.D. Mcdonald, Y.Q. Wu, J. Read, Q.F. Gu, Scr. Mater. 65, 10 (2011)CrossRefGoogle Scholar
  26. 26.
    K.N. Tu, R.D. Thompson, Acta Mater. 30, 5 (1982)CrossRefGoogle Scholar
  27. 27.
    M.S. Park, S.L. Gibbons, R. Arroyave, J. Electron. Mater. 43, 7 (2014)Google Scholar
  28. 28.
    L. Yin, G. Electric, J. Mater. Res. 26, 3 (2016)Google Scholar
  29. 29.
    G. Ross, X. Tao, M. Broas, N. Mäntyoja, V. Vuorinen, A. Graff, F. Altmann, M. Petzold, M. Paulasto-kröckel, J. Electron. Mater. Lett. 13, 4 (2017)Google Scholar
  30. 30.
    K. Chen, D. Wang, H. Ling, A. Hu, M. Li, W. Zhang, L. Cao, J. Mater. Sci.: Mater. Electron. 29, 22 (2018)Google Scholar

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© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Electrochemical Microfabrication LaboratoryIndian Institute of Technology BombayMumbaiIndia

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