Journal of Electronic Materials

, Volume 38, Issue 6, pp 828–833

Viscosity and Surface Tension of Liquid Sn-Cu Lead-Free Solders


The viscosity of Sn-0.7wt.%Cu and Sn-2wt.%Cu lead-free solders was measured using a torsional oscillation viscometer from 503 K to 773 K. For both melts the viscosity decreased with increasing temperature, and the values dropped abruptly at certain temperature ranges, i.e., 553 K to 573 K for Sn-0.7Cu and 573 K to 603 K for Sn-2Cu. Correspondingly, two segments, a low-temperature zone and a high-temperature zone, were found on both ηT and ln η–1/T plots, where η is the viscosity and T is the absolute temperature. The activation energy ε and the unit volume of flow νm were obtained by applying the parameters of linear fitting for each temperature zone. The surface tension of the solders was calculated using the measured viscosity values, and the results were checked by measuring the wetting angles of metallurgical reactions between the solders and the Cu substrates. Both viscosity and surface tension are closely related to the liquid structure of the solder alloy.


Lead-free solder Sn-Cu alloy viscosity surface tension wetting␣property 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    K·N. Tu, A.M. Gusak and M. Li, J. Appl. Phys. 93, 1335 (2003). doi:10.1063/1.1517165 CrossRefADSGoogle Scholar
  2. 2.
    M. Abtew and G. Selvaduray, Mater. Sci. Eng. Rep. 27, 95 (2000). doi:10.1016/S0927-796X(00)00010-3 CrossRefGoogle Scholar
  3. 3.
    C.M.L. Wu, D.Q. Yu, C.M.T. Law and L. Wang, Mater. Sci. Eng. Rep. 44, 1 (2004). doi:10.1016/j.mser.2004.01.001 CrossRefGoogle Scholar
  4. 4.
    B. Trumble, IEEE Spectrum 35, 55 (1998). doi:10.1109/6.669978 CrossRefGoogle Scholar
  5. 5.
    J.X. Hou, H.X. Guo, C·W. Zhan, X.L. Tian and X.C. Chen, Mater. Lett. 60, 2038 (2006). doi:10.1016/j.matlet.2005.12.108 CrossRefGoogle Scholar
  6. 6.
    J.L. Wang, Microelectron. Reliab. 42, 293 (2002). doi:10.1016/S0026-2714(01)00231-1 CrossRefGoogle Scholar
  7. 7.
    Y.Y. Sun, Z.Q. Zhang and C·P. Wong, Macromol. Mater. Eng. 290, 1204 (2005). doi:10.1002/mame.200500149 CrossRefADSGoogle Scholar
  8. 8.
    X.Q. Wei, L. Zhou, H.Z. Huang and H·B. Xiao, Mater. Lett. 59, 1889 (2005). doi:10.1016/j.matlet.2005.02.005 CrossRefGoogle Scholar
  9. 9.
    I. Egry, G. Lohöfer and S. Sauerland, J. Non-Cryst. Solids 156-158, 830 (1993). doi:10.1016/0022-3093(93)90079-D CrossRefGoogle Scholar
  10. 10.
    Y.Q. Wu, X.F. Bian, T. Mao, X.L. Li, T.B. Li and C.D. Wang, Phys. Lett. A 361, 265 (2007). doi:10.1016/j.physleta.2006.09.035 MATHCrossRefADSGoogle Scholar
  11. 11.
    T. Siewert, S. Liu, D.R. Smith, and J.C. Madeni, Properties of Lead-Free Solders, Release 4.0 (National Institute of Standards and Technology (NIST), Boulder, CO; Colorado School of␣Mines, 2002).
  12. 12.
    Z. Li, S. Knott, P. Terzieff, and A. Mikula, TMS Annual Meeting 2006, March 12–16, 2006, San Antonio, TX, USAGoogle Scholar
  13. 13.
    Y. Plevachuk, V. Sklyarchuk, W. Hoyer, I. Kaban, J. Mater. Sci. 41, 4632 (2006). doi:10.1007/s10853-006-0053-4 CrossRefADSGoogle Scholar
  14. 14.
    N. Zhao, X.M. Pan, H.T. Ma, C. Dong, S·H. Guo, W. Lu and L. Wang, J. Phys.: Conf. Ser. 98, 012029 (2008). doi:10.1088/1742-6596/98/1/012029 CrossRefGoogle Scholar
  15. 15.
    D.Q. Yu and L. Wang, J. Alloy Compd. 458, 542 (2008). doi:10.1016/j.jallcom.2007.04.047 CrossRefGoogle Scholar
  16. 16.
    D.Q. Yu, C.M.L. Wu, D.P. He, N. Zhao, L. Wang and J.K.L. Lai, J. Mater. Res. 20, 2205 (2005). doi:10.1557/JMR.2005.0275 CrossRefADSGoogle Scholar
  17. 17.
    E.G. Schvidkovskii, Gostekhteorizda (Moscow: Science, 1955).Google Scholar
  18. 18.
    S. Nishimura, S. Matsumoto and K. Terashima, J. Cryst. Growth 237-239, 1667 (2002). doi:10.1016/S0022-0248(01)02317-X CrossRefGoogle Scholar
  19. 19.
    T. Iida and R.I.L. Guthrie, The Physical Properties of Liquid Metals (Oxford: Clarendon, 1988).Google Scholar
  20. 20.
    I. Egry, Scripta Metall. Mater. 28, 1273 (1993). doi:10.1016/0956-716X(93)90467-7 CrossRefGoogle Scholar
  21. 21.
    N. Saunders and A.P. Miodownik, Bull. Alloy Phase Diagrams 11, 278 (1990).CrossRefGoogle Scholar
  22. 22.
    J.H. Vincent, B·P. Richards, D.R. Wallis, I.A. Gunter, M. Warwick, H.A.H. Steen, P.G. Harris, M.A. Whitmore, S.R. Billington, A.C. Harman and E. Knight, Circuit World 19, 32 (1993). doi:10.1108/eb046210 CrossRefGoogle Scholar

Copyright information

© TMS 2009

Authors and Affiliations

  1. 1.School of Materials Science and EngineeringDalian University of TechnologyDalianChina
  2. 2.Institute of MicroelectronicsA*STAR (Agency for Science, Technology and Research)SingaporeSingapore

Personalised recommendations