Abstract
The mechanical behavior of Sn-rich solder/Cu joints is highly sensitive to processing variables such as solder reflow time, cooling rate, and subsequent thermal aging. In this article, we focus on the lap shear behavior of Sn-3.5Ag/Cu joints as a function of solder yield strength and intermetallic thickness. Experimental results showed that the shear strength of the solder joints is primarily controlled by the mechanical properties of the solder, and not the intermetallic thickness. The thickness of intermetallic, however, controlled the fracture mode of the solder joints. At intermetallic thicknesses greater than 20 µm, brittle fracture between Cu6Sn5 and Cu3Sn was the most common failure mechanism. Finite-element simulations were carried out to evaluate the effect of solder properties and of intermetallic thickness and morphology on lap shear behavior. The finite-element simulations corroborated the experimental findings, i.e., that increased solder strength results in increased joint strength. The simulations also showed that thicker intermetallics, especially of nodular morphology, yielded higher local plastic shear strain and work hardening rate.
Similar content being viewed by others
References
M. Abtew and G. Selvaduray: Mater. Sci. Eng. R: Rep., 2000, vol. 27, pp. 95–141.
E.P. Wood and K.L. Nimmo: J. Electron. Mater., 1994, vol. 23, pp. 709–13.
J. Glazer: J. Electron. Mater., 1994, vol. 23, pp. 693–700.
W. Yang, L.E. Felton, and R.W. Messler: J. Electron. Mater., 1995, vol. 24, pp. 1465–72.
S. Yu, M. Hon, and M. Wang: J. Electron. Mater., 2000, vol. 29, pp. 237–43.
H. Lee, M. Chen, H. Jao, and T. Liao: Mater. Sci. Eng. A, 2003, vol. 358, pp. 134–41.
D.R. Frear: JOM, 1996, vol. 48 (5), pp. 49–53.
D.R. Frear and P.T. Vianco: Metall. Trans. A, 1994, vol. 25A, pp. 1509–23.
C.W. Hwang and K. Suganuma: Mater. Sci. Eng. A, 2004, vol. 373, pp. 187–94.
K.N. Tu and R.D. Thompson: Acta Metall., 1982, vol. 30 (5), pp. 947–52.
X. Deng, G. Piotrowski, J.J. Williams, and N. Chawla: J. Electron. Mater., 2003, vol. 32, pp. 1403–13.
K.H. Prakash and T. Sritharan: Acta Mater., 2001, vol. 49, pp. 2481–89.
W.K. Choi and H.M. Lee: J. Electron. Mater., 2000, vol. 29, pp. 1207–13.
F. Guo, S. Choi, J.P. Lucas, and K.N. Subramanian: J. Electron. Mater., 2000, vol. 29, pp. 1241–48.
D. Ma, W.D. Wang, and S.K. Lahiri: J. Appl. Phys., 2002, vol. 91, pp. 3312–17.
C.R. Kao: Mater. Sci. Eng., 1997, vol. A238, pp. 196–201.
A. Hayashi, C.R. Kao, and Y.A. Chang: Scripta Mater., 1997, vol. 37, pp. 393–98.
S. Chada, R.A. Fournelle, W. Laub, and D. Shangguan: J. Electron. Mater., 2000, vol. 29, pp. 1214–21.
Z. Mei, A.J. Sunwoo, and J.W. Morris, Jr.: Metall. Trans. A, 1992, vol. 23A, pp. 857–64.
W.K. Choi and H.M. Lee: J. Electron. Mater., 2000, vol. 29, pp. 1207–13.
Y.C. Chan, A.C.K. So, and J.K.L. Lai: Mater. Sci. Eng. B, 1998, vol. 55, pp. 5–13.
H.L.J. Pang, K.H. Tan, X.W. Shi, and Z.P. Wang: Mater. Sci. Eng. A, 2001, vol. 307, pp. 42–50.
Hui-Wei Miao and Jenq-Gong Duh: Mater. Chem. Phys., 2001, vol. 71, pp. 255–71.
F. Ochoa, J.J. Williams, and N. Chawla: JOM, 2003, vol. 55 (6), pp. 56–60.
F. Ochoa, J.J. Williams, and N. Chawla: J. Electron. Mater., 2003, vol. 32, pp. 1414–20.
P. Protsenko, A. Terlain, V. Traskine, and N. Eustathopoulos: Scripta Mater., 2001, vol. 45, pp. 1439–45.
R.E. Pratt, E.I. Stromswold, and D.J. Quesnel: J. Electron. Mater., 1994, vol. 23 (4), pp. 375–82.
C.K. Alex and Y.C. Chan: IEEE Trans. CPMT-B, 1996, vol. 19 (3), pp. 661–68.
P.L. Tu, Y.C. Chan, and J.K.L. Lai: IEEE Trans. CPMT-B, 1997, vol. 20 (1), pp. 87–93.
W.W. Mullins: J. Appl. Phys., 1957, vol. 28, pp. 333–39.
R.J. Fields and S.R. Low: http://www.metallurgy.nist.gov/mechanical_properties/solder_paper.html.
Y.C. Chan, D.J. Xie, and J.K.L Lai: Mater. Sci. Eng. B, 1996, vol. 38, pp. 53–61.
B.A. Cook, I.E. Anderson, J.L. Harringa, R.L. Terpstra, J.C. Foley, O. Unal, and F.C. Laabs: J. Electron. Mater., 2001, vol. 30, pp. 1214–21.
T. Lee, J. Lee, and I. Jung: Microelectronics and Reliability, 1998, vol. 38 (12), pp. 1941–47.
T. Reinikainen, M. Poech, M. Krumm, and J. Kivilahti: Trans. ASME, 1998, vol. 120, pp. 106–13.
E.P. Busso, M. Kitano, and T. Kumazawa: ASME J. Electron. Packaging, 1994, vol. 116, pp. 6–15.
N. Paydar, Y. Tong, and H.U. Akay: ASME J. Electron. Packaging, 1994, vol. 116, pp. 265–73.
X. Deng: Arizona State University, Tempe, AZ, unpublished research, 2004.
X. Deng, M. Koopman, N. Chawla, and K.K. Chawla: Mater. Sci. Eng., 2004, vol. 364, pp. 241–43.
X. Deng, N. Chawla, K.K. Chawla, and M. Koopman: Acta Mater., 2004, vol. 52, pp. 4291–4303.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Deng, X., Sidhu, R.S., Johnson, P. et al. Influence of reflow and thermal aging on the shear strength and fracture behavior of Sn-3.5Ag solder/Cu joints. Metall Mater Trans A 36, 55–64 (2005). https://doi.org/10.1007/s11661-005-0138-8
Received:
Issue Date:
DOI: https://doi.org/10.1007/s11661-005-0138-8