Measurement of impact toughness of eutectic SnPb and SnAgCu solder joints in ball grid array by mini-impact tester

Abstract

The most frequent cause of failure for wireless, handheld, and portable consumer electronic products is an accidental drop to the ground. The impact may cause interfacial fracture of ball-grid-array solder joints. Existing metrology, such as ball shear and ball pull tests, cannot characterize the impact-induced high speed fracture failure. In this study, a mini-impact tester was utilized to measure the impact toughness and to characterize the impact reliability of both eutectic SnPb and SnAgCu solder joints. The annealing effect at 150 °C on the impact toughness was investigated, and the fractured surfaces were examined. The impact toughness of SnAgCu solder joints with the plating of electroless Ni/immersion Au (ENIG) became worse after annealing, decreasing from 10 or 11 mJ to 7 mJ. On the other hand, an improvement of the impact toughness of eutectic SnPb solder joints with ENIG was recorded after annealing, increasing from 6 or 10 to 15 mJ. Annealing has softened the bulk SnPb solder so that more plastic deformation can occur to absorb the impact energy.

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References

  1. 1

    K. Mishiro, S. Ishikawa, M. Abe, T. Kumai, Y. Higashiguchi K. Tsubone: Effect of the drop impact on BGA/CSP package reliability. Miroelectr. Reliab. 42, 77 2002

    Article  Google Scholar 

  2. 2

    M. Nishiura, A. Nakayama, S. Sakatani, Y. Kohara, K. Uenishi K. Kobayashi: Mechanical strength and microstructure of BGA joints using leadfree solders. Mater. Trans. 43, 1802 2002

    CAS  Article  Google Scholar 

  3. 3

    T-C. Chiu, K. Zeng, R. Stierman, D. Edwards K. Ano: Effect of aging on board level drop reliability for Pb-free BGA packages in Proc. 54th Electr. Compon. Technol. Conf. IEEE Piscataway, NJ 2004 1256–1262

  4. 4

    K. Zeng, R. Stierman, T-C. Chiu, D. Edwards, K. Ano K.N. Tu: Kirkendall void formation in eutectic SnPb solder joints on bare Cu and its effect on joint reliability. J. Appl. Phys. 97, 024508 2005

    Google Scholar 

  5. 5

    M. Date, T. Shoji, M. Fujiyoshi, K. Sato K.N. Tu: Ductile-to-brittle transition in Sn–Zn solder joints measured by impact test. Scripta Mater. 51, 641 2004

    CAS  Article  Google Scholar 

  6. 6

    T. Shoji, K. Yamamoto, R. Kajiwara, T. Morita, K. Sato M. Date: Proc. 16th JIEP Annual Meeting, Japan Institute of Electronics Packaging 2002 97

  7. 7

    J.M. Holt: Charpy Impact Test: Factors and Variables ASTM STP 1072, Philadelphia, PA 1990

    Google Scholar 

  8. 8

    R.J. Coyle, P.P. Solan, A.J. Serafino S.A. Gahr: The influence of room temperature aging on ball shear strength and microstructure of area array solder balls in Proc. 50th Electr. Compon. Technol. Conf. IEEE Piscataway, NJ 2000 160

  9. 9

    Z. Chen, M. He G. Qi: Morphology and kinetic study of the interfacial reaction between the Sn–3.5Ag solder and electroless Ni–P metallization. J. Electron. Mater. 33, 1465 2004

    CAS  Article  Google Scholar 

  10. 10

    J.W. Jang, P.G. Kim, K.N. Tu, D.R. Frear P. Thompson: Solder reaction assisted crystallization of electroless Ni–P under bump metallization in low cost flip chip technology. J. Appl. Phys. 85, 8456 1999

    CAS  Article  Google Scholar 

  11. 11

    K. Harada, S. Baba, Q. Wu, H. Matsushima, T. Matsunaga, Y. Uegai M. Kimura: Analysis of solder joint fracture under mechanical bending test in Proc. 53rd Electr. Comp. Technol. Conf. IEEE Piscataway, NJ 2003 1731–1737

  12. 12

    H. Matsuki, H. Ibuka H. Saka: TEM observation of interfaces in a solder joint in a semiconductor device. Sci. Technol. Adv. Mater. 3, 261 2002

    CAS  Article  Google Scholar 

  13. 13

    W. Peng, E. Monlevade M.E. Marques: Effect of thermal aging on interfacial microstructure and growth of intermetallic compounds between OSP Cu and SnAgCu solder. Microelectr. Reliab. 47, 2161 2007

    CAS  Article  Google Scholar 

  14. 14

    Y-C. Sohn J. Yu: Correlation between chemical reaction and brittle fracture found in electroless Ni(P)/immersion gold–solder interconnection. J. Mater. Res. 20, 1931 2005

    CAS  Article  Google Scholar 

  15. 15

    L. Snugovsky, D.D. Perovic J.W. Rutter: Experiments on the aging of Sn–Ag–Cu solder alloys. Powder Metall. 48, 193 2005

    CAS  Article  Google Scholar 

  16. 16

    C-W. Hwang, K. Suganuma, M. Kiso S. Hashimoto: Interface microstructures between Ni–P alloy plating and Sn–Ag–(Cu) lead-free solders. J. Mater. Res. 18, 2540 2003

    CAS  Article  Google Scholar 

  17. 17

    K. Zeng K.N. Tu: Six cases of reliability study of Pb-free solder joints in electronic packaging technology. Mater. Sci. Eng., R 38, 55 2002

    Article  Google Scholar 

  18. 18

    H. Kim, M. Zhang, C.M. Kumar, D. Suh, P. Liu, D. Kim, M. Xie Z. Wang: Improved drop reliability performance with lead free solders of low ag content and their failure modes in Proc. 57th Electron. Comp. Technol. Conf. IEEE Piscataway, NJ 2007 962–967

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Acknowledgments

This study was supported by cooperation between Texas Instruments, Inc. and University of California at Los Angeles, and by a UC-Discovery Grant (Project No. ELE 03-10185). Special thanks go to the paper reviewers for their kind, helpful comments.

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Correspondence to Kejun Zeng.

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Xu, Y., Ou, S., Tu, K. et al. Measurement of impact toughness of eutectic SnPb and SnAgCu solder joints in ball grid array by mini-impact tester. Journal of Materials Research 23, 1482–1487 (2008). https://doi.org/10.1557/JMR.2008.0186

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