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Effect of Sample Size on the Solidification Temperature and Microstructure of SnAgCu Near Eutectic Alloys

Published online by Cambridge University Press:  03 March 2011

R. Kinyanjui
Affiliation:
Department of Physics and Materials Science Program, Binghamton University, Binghamton, New York 13902
L.P. Lehman
Affiliation:
Department of Physics and Materials Science Program, Binghamton University, Binghamton, New York 13902
L. Zavalij
Affiliation:
Department of Physics and Materials Science Program, Binghamton University, Binghamton, New York 13902
E. Cotts
Affiliation:
Department of Physics and Materials Science Program, Binghamton University, Binghamton, New York 13902
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Abstract

The degree of undercooling of Sn in near eutectic, SnAgCu solder balls upon cooling at a rate of 1 °C/s from the melt was examined and found to increase linearly with inverse nominal sample diameter (for balls of radius between 100 and 1000 μm). The mean undercooling for SnAgCu solder balls in a flip chip assembly was 62 °C. The microstructures of these different samples were examined by means of scanning electron microscopy. The Sn dendrite arm width was observed to monotonically increase with ball diameter, indicating a possible dependence of the mechanical response of such solder balls upon size.

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Articles
Copyright
Copyright © Materials Research Society 2005

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References

REFERENCES

1Tian, Y., Wu, P.E. Jiang, and T. Ando, : Heterogeneous nucleation and solidification prediction of Sn–5wt% Pb droplets. Chin. Phys. Lett. 21, 207 (2004).Google Scholar
2Turnbull, D.: Kinetics of solidification of supercooled liquid mercury droplets. J. Chem. Phys. 20, 411 (1952).CrossRefGoogle Scholar
3Pederson, A.S., Pryds, N.S. Linderoth, P.H. Larsen, and J. Kjoller, : The determination of dynamic and equilibrium solid/liquid transformation data for Sn–Pb using DSC. J. Therm. Anal. Cal. 64, 887 (2001).CrossRefGoogle Scholar
4Zhang, Z., Li, J.C. and Q. Jiang, : Size effect on the freezing temperature of lead particles. J. Mater. Sci. Let. 19, 1893 (2000).CrossRefGoogle Scholar
5Cantor, B.: Embedded droplet measurements and an adsorption model of the heterogeneous nucleation of solidification. Mater. Sci. Eng. A178, 225 (1994).CrossRefGoogle Scholar
6Green, N.R., Charles, J.A. and G.C. Smith, : Solidification and microstructure of Pb-Sn microsolder bonds. Mater. Sci. Technol. 10, 977 (1994).CrossRefGoogle Scholar
7Boswell, P.G. and Chadwick, G.A.: Heterogeneous nucleation in entrained Sn droplets. Acta Metall. 28, 209 (1980).CrossRefGoogle Scholar
8Trivedi, R., Jin, F. and  Anderson, I.E.: Dynamical evolution of microstructure in finely atomized droplets of Al–Si alloys. Acta Mater. 51, 289 (2003).CrossRefGoogle Scholar
9Lu, Y. and Wei, B.: A transition from eutectic to dendritic growth induced by high undercooling conditions. Chin. Phys. Lett. 20, 1379 (2003).Google Scholar
10Han, X.J., Wang, N. and  Wei, B.: Rapid eutectic growth under containerless condition. Appl. Phys. Lett. 81, 778 (2002).CrossRefGoogle Scholar
11Sa, F., Rocha, O.L. Siqueira, C.A. and  Garcia, A.: The effect of solidification variables on tertiary dendrite arm spacing in unsteady-state directional solidification of Sn–Pb and Al–Cu alloys. Mater. Sci. Eng. A373, 131 (2004).CrossRefGoogle Scholar
12Sheng, H.W., Lu, K. and  Ma, E.: Melting and freezing behavior of embedded nanoparticles in ball-milled Al–10 wt% M (M = In, Sn, Bi, Cd, Pb) Mixtures. Acta Mater. 46, 5195 (1998).CrossRefGoogle Scholar
13De Castro, W.B., de Maia, M. Lucena Kiminami, C.S. and  Bolfarini, C.: Microstructure of undercooled Pb–Sn alloys. Mater. Res. 4, 83 (2001).CrossRefGoogle Scholar
14de Oliveira, M.F., Caram, R. and  Kiminami, C.S.: Microstructure of undercooled SnSe–SnSe2 hypoeutectic alloy. J. Alloys Compd 375, 142 (2004).CrossRefGoogle Scholar
15Cao, H. and Wessen, M.: Effect of microstructure on mechanical properties of as-cast Mg–Al alloys. Metall. Mater. Trans 35A, 309 (2004).CrossRefGoogle Scholar
16Li, M. and Kuribayashi, K.: Nucleation-controlled microstructures and anomalous eutectic formation in undercooled Co–Sn and Ni–Si eutectic melts. 34A, 2999 (2003).CrossRefGoogle Scholar
17Kim, 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. A333, 106 (2002).CrossRefGoogle Scholar
18Perepezko, J.H.: Nucleation reactions in undercooled liquids. Mater. Sci. Eng. A178, 105 (1994).CrossRefGoogle Scholar
19Trivedi, R., Magnin, P. and Kurz, W.: Theory of eutectic growth under rapid solidification conditions. Acta Metall. 35, 971 (1987).CrossRefGoogle Scholar
20Henderson, 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
21Lehman, L.P., Atavale, S.N. Fullem, T.Z. Giamis, A.C. Kinyanjui, R.K. Lowenstein, M. Mather, K. Patel, R. Rae, D. Wang, J. Xing, Y. Zavalij, L. Borgesen, P. and  Cotts, E.J.: Growth of Sn and intermetallic compounds in Sn–Ag–Cu solder. J. Electron. Mater 33(2004).CrossRefGoogle Scholar
22Sundquist, B.E. and Mondolfo, L.F.: Heterogeneous nucleation in the liquid-to-solid transformation in alloys. Trans. Metall. Soc. AIME 221, 157 (1961).Google Scholar
23Shukla, P., Mandal, R.K. and  Ohja, S.N.: Non-equilibrium solidification of undercooled droplets during atomization process. Bull. Mater. Sci. 24, 547 (2001).CrossRefGoogle Scholar
24Moon, K.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
25Ochoa, F., Williams, J.J. and  Chawla, N.: Effects of cooling rate on the microstructure of and tensile behavior of a Sn–3.5 Ag wt% solder. JEM 32 12(2003).CrossRefGoogle Scholar
26Chromik, R. and Cotts, E.J.: The kinetics and energetics of solid state reactions in Cu/Si multilayered thin films. J. Appl. Phys. 86, 4273 (1999).CrossRefGoogle Scholar
27Feder, K., Gance, K. and Cotts, E.J.: Calorimetric study of solid state reactions. Pure Appl. Chem. 65, 895 (1993).CrossRefGoogle Scholar