Abstract
As solder joints become increasingly miniaturized to meet the severe demands of future electronic packaging, it is vitally important to consider whether the solder joint size and geometry could become reliability issues and thereby affect implementation of the Pb-free solders. In this study, three bumping techniques, i.e., solder dipping, stencil printing followed by solder reflow, and electroplating of solders with subsequent reflow, were used to investigate the interfacial interactions of molten Sn-3.5Ag, Sn-3.8Ag-0.7Cu, and pure Sn solders on a copper pad at 240°C. The resultant interfacial microstructures, coming from a variety of Cu pads, with sizes ranging from 1 mm to 25 µm, and representing different solder bump geometries, have been investigated. In addition, a two-dimensional thermodynamic/kinetic model has been developed to assist the understanding of the kinetics of interdiffusion and the formation of interfacial intermetallic compounds. Experimental results and theoretical predictions both suggest that the solder bump size and geometry can influence the as-soldered microstructure; therefore, this factor should be taken into consideration for the design of future reliable ultrafine Pb-free solder joints.
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References
K. Suganuma, Curr. Opin. Solid State Mater. 5, 55 (2001).
Y.G. Lee and J.G. Duh, J. Mater. Sci.-Mater. Electron. 10, 33 (1999).
K.H. Prakash and T. Sritharan, Acta Mater. 49, 2481 (2001).
M. Shaefer, W. Laub, J.M. Sabee, and R.A. Fournelle, J. Electron. Mater. 25, 992 (1996).
J.K. Kivilahti, JOM 54, 52 (2002).
J.W. Morris, J. Kor. Phys. Soc. 35, S335 (1999).
Z. Huang, P.P. Conway, C. Liu, and R.C. Thomson, J. Mater. Res. 20, 649 (2005).
M. Schaefer, R.A. Fournelle, and J. Liang, Design and Reliability of Solder and Solder Interconnections, ed. R.K. Mahidhara, D.R. Frear, S.M.L. Sastry, K.L. Murtym, P.K. Liaw, and W. Winterbottom (Warrendale, PA: TMS, 1997), p. 247.
S. Chada, W. Laub, R.A. Fournelle, and D. Shangguan, J. Electron. Mater. 28, 1194 (1999).
S. Chada, R.A. Fournelle, W. Laub, and D. Shangguan, J. Electron. Mater. 29, 1214 (2000).
D. Ma, W.D. Wang, and S.K. Lahiri, J. Appl. Phys. 91, 3312 (2002).
W.K. Choi, S.K. Kang, and D.Y. Shih, J. Electron. Mater. 31, 1283 (2002).
A. Sharif, Y.C. Chan, and R.A. Islam, Mater. Sci. Eng. B106, 120 (2004).
M.N. Islam, A. Sharif, and Y.C. Chan, J. Electron. Mater. 34, 143 (2005).
Z. Huang, P.P. Conway, C. Liu, and R.C. Thomson, J. Electron. Mater. 33, 1227 (2004).
H.G. Song, J.W. Morris, and M.T. McCormack, J. Electron. Mater. 29, 1038 (2000).
B. Salam, N.N. Ekere, and D. Rajkumar, Proc. 51st Electron. Compon. Technol. Conf. 471 (2001).
R.H. Davies, A.T. Dinsdale, T.G. Chart, T.I. Barry, and M.H. Rand, High Temp. Sci. 26, 251 (1989).
R.H. Davies, A.T. Dinsdale, J.A. Gisby, J.A.J. Robinson, and S.M. Martin, CALPHAD 26, 229 (2002).
MATLAB Programming (Natick, MA: The MathWorks, Inc., 2004).
FEMLAB 3 User’s Guide (Stockholm: COMSOL AB, 2004).
A. Sharif and Y.C. Chan, J. Electron. Mater. 34, 46 (2005).
M.L. Huang, T. Loeher, A. Ostmann, and H. Reichl, Proc. MicroTech 2005: Low-Cost Electronic Packaging for Tomorrow’s Applications (Cambridge, England: IMAPS UK, 2005).
J. Bath, H. Ahluwalla, K. Chagger, and K. Nimmo, Dissolution and Intermetallic Growth Rates of Gold, Silver, Palladium, Copper, Iron and Nickel in Molten Tin-Lead and Lead-Free Solders, Soldertec Research Report (2000).
J.W. Morris, J.L. Freer Goldstein, and Z. Mie, The Mechanics of Solder Alloy Interconnects, ed. D.R. Frear, S.N. Burchett, H.S. Morgan, and J.H. Lau (New York: Van Nostrand Reinhold, 1994), p. 15.
R.J. Klein Wassink, Soldering in Electronics, 2nd ed. (Scotland: Electrochemical Publications Ltd., 1989), p. 155.
L.P. Lehman et al, J. Electron. Mater. 33, 1429 (2004).
S.K. Kang, D.Y. Shih, D. Leonard, D.W. Henderson, T. Gosselin, S.I. Cho, J. Yu, and W.K. Choi, JOM 56, 34 (2004).
S.K. Kang, W.K. Choi, D.Y. Shih, D.W. Henderson, T. Gosselin, A. Sarkhel, C. Goldsmith, and K.J. Puttlitz, JOM 55, 61 (2003).
D.W. Henderson, T. Gosselin, A. Sarkhel, S.K. Kang, W.K. Choi, D.Y. Shih, C. Goldsmith, and K.J. Puttlitz, J. Mater. Res. 17, 2755 (2002).
K.W. Moon, W.J. Boettinger, U.R. Kitten, F.S. Biancaniello, and C.A. Handwerker, J. Electron. Mater. 29, 1122 (2000).
I. Ohnuma, M. Miyashita, K. Anzai, X.J. Liu, H. Ohtani, R. Kainuma, and K. Ishida, J. Electron. Mater. 29, 1137 (2000).
K.J. Rönkä, F.J.J. van Loo, and J.K. Kivilahti, Scripta Mater. 37, 1575 (1997).
K.J. Rönkä, F.J.J. van Loo, and J.K. Kivilahti, Metall. Mater. Trans. A 29, 2951 (1998).
C. Wagner, Acta Metall. 17, 99 (1969).
B.-J. Lee, N.M. Hwang, and H.M. Lee, Acta Mater. 45, 1867 (1997).
K.N. Tu, J.W. Mayer, and L.C. Feldman, Electronic Thin Film Science for Electrical Engineers and Materials Scientists (New York: Macmillan Publishing Company, 1992), p. 313.
M. Faizan, R.A. McCoy, D.C. Lin, T.S. Srivatsan, and G.X. Wang, Proc. ASME Summer Heat Transfer Conference, Las Vegas, 2003 (ASME, 2003), p. 289.
S. Däbritz, D. Bergner, and V. Hoffmann, Defect Diffus. Forum 143–147, 579 (1997).
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Huang, Z., Conway, P.P., Jung, E. et al. Reliability issues in Pb-free solder joint miniaturization. J. Electron. Mater. 35, 1761–1772 (2006). https://doi.org/10.1007/s11664-006-0231-9
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DOI: https://doi.org/10.1007/s11664-006-0231-9