Abstract
Use of bilayered Pb-Sn solders consisting of high Sn and high Pb solder compositions is an option for joining chips to organic substrates at lower temperatures in which the high Sn solder is deposited onto Cu pads on the substrates. In this work interactions between the two-layered solder and copper pads during the reflow operation have been studied for both flip chip and Ball Grid Array (BGA) applications. It has been observed that Sn from the high Sn solder migrates faster at the edges along the surface of the high Pb solder than at the interior, resulting in a non-uniform Sn concentration along the Cu-solder interface. The thickness of the intermetallic compound formed due to the interaction of Cu and Sn has also been found to be non-uniform along the solder-Cu interface. This has been attributed to the variation in the Sn concentration of the solder adjacent to the Cu pads at different positions. The intermetallic compound growth rate has been explained using a model based on Sn diffusion into copper.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
R.R. Tummala and E.J. Rymaszewski, Microelectronics Packaging Handbook, Part II: Semiconductor Packaging (New York: Chapman and Hall, 1997), pp. 11–14.
D.O. Powell and A.K. Trivedi, Proc. 43rd IEEE Electronic and Components and Technol. Conf. (New York: IEEE, 1993), pp. 182–186.
Y. Tsukada, S. Tsuchida, and Y. Mashimoto, Proc. 42nd IEEE Electronic Components Technol. Conf. (New York: IEEE, 1992), pp. 22–27.
K.N. Tu, Acta Metall. 21, 347 (1973).
S.F. Dirnfeld and J.J. Ramon, Welding J. Res. Suppl. 69, 373s (1990).
D.R. Frear, F.M. Hosking, and P.T. Vianco, Materials Developments in Microelectronic Packaging Conf. Proc., ed. P.J. Singh (Metals Park, OH: ASM, 1991), pp. 229–240.
M. Schaefer, R.A. Fournelle, and Jin Liang, J. Electron. Mater. 27, 1167 (1998).
D.R. Frear and P.T. Vianco, Metall. Mater. Trans. A 25A, 1509 (1994).
A.S. Zuruzi, C.-H. Chiu, W.T. Chen, S.K. Lahiri, and K.N. Tu (Paper presented at the Materials Research Society Spring 1999 Meeting, San Francisco, 5–9 April 1999).
M. Onishi and H. Fujibuchi, Trans. JIM 16, 539 (1975).
P.T. Vianco, P. Hlava, and A.C. Kilgo, J. Electron. Mater. 23, 583 (1994).
P.T. Vianco, K.L. Erickson, and P.L. Hopkins, J. Electron. Mater. 23, 727 (1994).
P.W. Dehaven, Materials Research Society Symp. Proc. Vol. 40, Electronic Packaging Materials Science, ed. E.A. Giess, K.N. Tu, and D.R. Uhlmann (Pittsburgh, PA: MRS, 1984).
H.K. Kim, H.K. Liou, and K.N. Tu, Appl. Phys. Lett. 66, 2337 (1995).
S.K. Kang and V. Ramachandran, Scripta Metall. 14, 421 (1980).
R.J. Klein-Wassink, Soldering in Electronics (Ayr, Scotland: Electrochemical Publications Ltd., 1989), Chapter 4.
W.H. Press, S.A. Teukolsky, W.T. Vetterling, and B.P. Flannery, Numerical Recipes in Fortran 77 (Cambridge, MA: Cambridge University Press, 1992), Chapter 15.
K. Kumar, A. Mosscaritolo, and M. Brownawell, J. Electrochem. Soc. 128, 2165 (1981).
H.D. Blair, T.Y. Pan, and J.M. Nicholson, Proc. 44th Electronic Components and Technol. Conf. (Piscataway, NJ: IEEE, 1998).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Zuruzi, A.S., Chiu, C.H., Lahiri, S.K. et al. Kinetics of copper and high Pb/high Sn bilayered Pb-Sn solder interactions. J. Electron. Mater. 28, 1224–1230 (1999). https://doi.org/10.1007/s11664-999-0161-4
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/s11664-999-0161-4