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The microstructure of Sn in near-eutectic Sn–Ag–Cu alloy solder joints and its role in thermomechanical fatigue

Published online by Cambridge University Press:  03 March 2011

Donald W. Henderson*
Affiliation:
IBM Corporation, Endicott, New York 13760
James J. Woods
Affiliation:
IBM Corporation, Endicott, New York 13760
Timothy A. Gosselin
Affiliation:
IBM Corporation, Endicott, New York 13760
Jay Bartelo
Affiliation:
IBM Corporation, Endicott, New York 13760
David E. King
Affiliation:
Endicott Interconnect Technologies, Endicott, New York 13760
T.M. Korhonen*
Affiliation:
Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853
M.A. Korhonen
Affiliation:
Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853
L.P. Lehman
Affiliation:
Physics Department, Materials Science Program, Binghamton University,Binghamton, New York 13902
E.J. Cotts
Affiliation:
Physics Department, Materials Science Program, Binghamton University,Binghamton, New York 13902
Sung K. Kang
Affiliation:
IBM Corporation, T.J. Watson Research Center, Yorktown Heights, New York 10598
Paul Lauro
Affiliation:
IBM Corporation, T.J. Watson Research Center, Yorktown Heights, New York 10598
Da-Yuan Shih
Affiliation:
IBM Corporation, T.J. Watson Research Center, Yorktown Heights, New York 10598
Charles Goldsmith
Affiliation:
IBM Corporation, Hopewell Junction, New York 12533
Karl J. Puttlitz
Affiliation:
IBM Corporation, Hopewell Junction, New York 12533
*
a) Address all correspondence to these authors. e-mail: [email protected], [email protected], [email protected]
a) Address all correspondence to these authors. e-mail: [email protected], [email protected], [email protected]
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Abstract

During the solidification of solder joints composed of near-eutectic Sn–Ag–Cu alloys, the Sn phase grows rapidly with a dendritic growth morphology, characterized by copious branching. Notwithstanding the complicated Sn growth topology, the Sn phase demonstrates single crystallographic orientations over large regions. Typical solder ball grid array joints, 900 μm in diameter, are composed of 1 to perhaps 12 different Sn crystallographic domains (Sn grains). When such solder joints are submitted to cyclic thermomechanical strains, the solder joint fatigue process is characterized by the recrystallization of the Sn phase in the higher deformation regions with the production of a much smaller grain size. Grain boundary sliding and diffusion in these recrystallized regions then leads to extensive grain boundary damage and results in fatigue crack initiation and growth along the recrystallized Sn grain boundaries.

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Articles
Copyright
Copyright © Materials Research Society 2004

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References

REFERENCES

1Moon, Z.W., Boettinger, W.J., Kattner, U.R., Biancaniello, F.S. and Handwerker, C.A.: Experimental and thermodynamic assessment of Sn–Ag–Cu solder alloys. J. Electron. Mater. 29, 1122 (2000).CrossRefGoogle Scholar
2Loomans, M.E. and Fine, M.E.: Tin silver copper eutectic temperature and compostion. Metall. Mater. Trans. A, Phys. Metall. Mater. Sci. 31A, 1155 (2000).CrossRefGoogle Scholar
3Ohnuma, I., Miyashita, M., Anzai, K., Liu, X.J., Ohtani, H., Kainuma, R. and Ishida, K.: Phase equilibria and the related properties of Sn–Ag–Cu based, Pb-free, solder alloys. J. Electron. Mater. 29, 1137 (2000).CrossRefGoogle Scholar
4Bartelo, J., Cain, S.R., Caletka, D., Darbha, K., Gosselin, T., Henderson, D.W., King, D., Knadle, K., Sarkhel, A., Thiel, G., Woychik, C., Shih, D-Y., Kang, S., Puttlitz, K., and Woods, J.: Proceedings, APEX 2001, January 14–18, San Diego, CA (2001) LF2-2. Published by: IPC SMEMA Council.Google Scholar
5Henderson, D.W., Gosselin, T., Sarkhel, A., Kang, S.K., Choi, W-K., Shih, D-Y., Goldsmith, C. and Puttlitz, K.J.: Ag3Sn plate formation in the solidification of near ternary eutectic Sn–Ag–Cu alloys. J. Mater. Res. 17, 2775 (2002).CrossRefGoogle Scholar
6Huh, S.H., Kim, K.S. and Suganuma, K.: Effect of Ag addition on the microstructural and mechanical properties of Sn–Cu eutectic solder. Mater. Trans. (Japan) 42, 739 (2001).CrossRefGoogle Scholar
7Kim, K.S., Huh, S.H. and Suganuma, K.: Effects of cooling speed on microstructure and tensile properties of Sn–Ag–Cu alloys. Mater. Sci. Eng. A 333, 106 (2002).CrossRefGoogle Scholar
8Lehman, L.P., Kinyanjui, R.K., Zavalij, L., Zribi, A., and Cotts, E.J.: Growth and selection of intermetallic species in Sn–Ag–Cu, No–Pb, solder systems, based on pad metallurgies and thermal histories. 53rd Electronic Components and Technology Conference, May 27–30, 2003, pp. 12151221.Google Scholar
9Rosenberg, A. and Winegard, W.C.: The rate of growth of dendrites in supercooled tin. Acta Metall. 2, 342 (1954).CrossRefGoogle Scholar
10Frear, D.R., Jang, J.W., Lin, J.K. and Zhang, C.: Pb-free solders for flip-chip interconnects. J. Met . 53, 28 (2001).Google Scholar
11Choi, S., Subramanian, K.N., Lucas, J.P. and Bieler, T.R.: Thermomechanical fatigue behavior of Sn–Ag solder joints. J. Electron. Mater. 29, 1249 (2000).CrossRefGoogle Scholar
12Telang, A.U., Bieler, T.R., Choi, S. and Subramanian, K.N.: Orientation imaging studies of Sn-based electronic solder joints. J. Mater. Res. 17, 2294 (2002).CrossRefGoogle Scholar
13Atroshenko, S.A. and Liu, D.R.: Dynamic recrystallization in solder under thermal cycling fatigue. Proceedings of the 21st Riso International Symposium on Materials Science, (Rico Natl. Lab, Roskilde, Denmark, 2000) p. 221.Google Scholar
14Zhao, J., Miyashita, Y. and Mutoh, Y.: Fatigue crack growth behavior of 95Pb-5Sn solder under various stress ratios and frequencies. Int. J. Fatigue 22, 665 (2000).CrossRefGoogle Scholar