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Evaluation of the microstructure and whisker growth in Sn–Zn–Ga solder with Pr content

Published online by Cambridge University Press:  24 May 2012

Huan Ye*
Affiliation:
College of Materials Science and Technology, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China; and Center for Advanced Life Cycle Engineering, University of Maryland, College Park, Maryland 20742
Songbai Xue
Affiliation:
College of Materials Science and Technology, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China
Michael Pecht
Affiliation:
Center for Advanced Life Cycle Engineering, University of Maryland, College Park, Maryland 20742
*
a)Address all correspondence to this author. e-mail: [email protected]
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Abstract

In spite of previous reports documented that many beneficial effects can be obtained by adding rare earth (RE) elements to Pb-free solders, this paper presents the risk of Sn whisker growth in the Sn–9Zn–0.5Ga Pb-free solders due to the addition of RE Pr. Results showed that solder microstructures are refined with the addition of trace amount of Pr. However, excessive Pr addition led to the formation of Pr–Sn intermetallic compounds (IMCs) and spontaneous growth of Sn whiskers on the IMC surfaces. It was found that the IMC size has a dramatic impact on whisker growth. Sn whiskers grew in slow-cooled solder with larger IMC particles are much longer and more prolific than that in fast-cooled solder with smaller IMC size. It was proposed that the driving force for whisker growth is originated from the oxidation of the RE-rich Pr–Sn IMCs. Our results indicated that the effects of RE on Pb-free solders should be reevaluated.

Type
Articles
Copyright
Copyright © Materials Research Society 2012

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References

REFERENCES

1.Choi, H., Lee, T.K., Kim, Y.S., Kwon, H., Tseng, C.F, Duh, J.G., and Choe, H.: Improved strength of boron-doped Sn-1.0Ag-0.5Cu solder joints under aging conditions. Intermetallics 20(1), 707712 (2012).CrossRefGoogle Scholar
2.Haseeb, A.S.M.A., and Leng, T.S.: Effects of Co nanoparticle addition to Sn-3.8Ag-0.7Cu solder on interfacial structure after reflow and ageing. Intermetallics 19(5), 707712 (2011).CrossRefGoogle Scholar
3.Luo, Z.B., Wang, L., Fu, Q.Q., Cheng, C.Q., and Zhao, J.: Formation of interfacial η′-Cu6Sn5 in Sn-0.7Cu/Cu solder joints during isothermal aging. J. Mater. Res. 26(12), 14681471 (2011).CrossRefGoogle Scholar
4.Ye, H., Xue, S.B., Zhang, L., Ji, F., and Dai, W.: Reliability evaluation of CSP soldered joints based on FEM and Taguchi method. Comput. Mater. Sci. 48(3), 509512 (2010).CrossRefGoogle Scholar
5.Chen, C.M., Hung, Y.M., Lin, C.P., and Su, W.C: Effect of temperature on microstructural changes of the Sn-9 wt% Zn lead-free solder stripe under current stressing. Mater. Chem. Phys. 115(1), 367370 (2009).CrossRefGoogle Scholar
6.Garcia, L.R., Osorio, W.R., Peixoto, L.C., and Garcia, A.: Mechanical properties of Sn-Zn lead-free solder alloys based on the microstructure array. Mater. Charact. 61(2), 212220 (2010).CrossRefGoogle Scholar
7.Wei, X.Q., Huang, H.Z., Zhou, L., Zhang, M., and Liu, X.D.: On the advantages of using a hypoeutectic Sn-Zn as lead-free solder material. Mater. Lett. 61(3), 655658 (2007).CrossRefGoogle Scholar
8.Lai, Y.S., Tong, H.M., and Tu, K.N.: Recent research advances in Pb-free solders. Microelectron. Reliab. 49(3), 221222 (2009).CrossRefGoogle Scholar
9.Zeng, K. and Tu, K.N.: Six cases of reliability study of Pb-free solder joints in electronic packaging technology. Mater. Sci. Eng., R 38(2), 55105 (2002).CrossRefGoogle Scholar
10.Shibutani, T., Wu, J., Yu, Q., and Pecht, M.: Key reliability concerns with lead-free connectors. Microelectron. Reliab. 48(10), 16131627 (2008).CrossRefGoogle Scholar
11.Fukuda, Y., Osterman, M., and Pecht, M.: The impact of electrical current, mechanical bending, and thermal annealing on tin whisker growth. Microelectron. Reliab. 47(1), 8892 (2007).CrossRefGoogle Scholar
12.Cheng, J., Vianco, P.T., Zhang, B., and Li, J.C.M.: Nucleation and growth of tin whiskers. Appl. Phys. Lett. 98(24), 184102 (2011).CrossRefGoogle Scholar
13.Xian, A.P. and Liu, M.: Observations of continuous tin whisker growth in NdSn3 intermetallic compound. J. Mater. Res. 24(9), 27752783 (2009).CrossRefGoogle Scholar
14.Arnold, S.M.: The growth of metal whiskers on electrical components. (In: Proc. of the IEEE Elec. Comp. Conf. 1959). pp. 7582.Google Scholar
15.Yu, A.M., Kim, J.K., Lee, J.H., and Kim, M.S.: Pd-doped Sn-Ag-Cu-In solder material for high drop/shock reliability. Mater. Res. Bull. 45(3), 359361 (2010).CrossRefGoogle Scholar
16.Zhang, L., Xue, S.B., Gao, L.L., Zeng, G., Sheng, Z., Chen, Y., and Yu, S.L.: Effects of rare earths on properties and microstructures of lead-free solder alloys. J. Mater. Sci. - Mater. Electron. 20(8), 115 (2011).Google Scholar
17.Shi, Y.W., Tian, J., Hao, H., Xia, Z.D., Lei, Y.P., and Guo, F.: Effects of small amount addition of rare earth Er on microstructure and property of SnAgCu solder. J. Alloys Compd. 453(2), (2008).CrossRefGoogle Scholar
18.Guo, F., Zhao, M.K., Xia, Z.D., Lei, Y.P., Li, X.Y., and Shi, Y.W.: Lead-free solders with rare earth additions. JOM 61(6), 3944 (2009).CrossRefGoogle Scholar
19.Yu, D.Q., Zhao, J., and Wang, L.: Vement on the microstructure stability, mechanical and wetting properties of Sn-Ag-Cu lead-free solder with the addition of rare earth elements. J. Alloys Compd. 376(2), 170175 (2004).CrossRefGoogle Scholar
20.Lin, S.K., Yang, C.F., Wu, S.H., and Chen, S.W.: Liquidus projection and solidification of the Sn-In-Cu ternary alloys. J. Electron. Mater. 37(4), 498506 (2008).CrossRefGoogle Scholar
21.Bhattacharya, S.K. and Baldwin, D.F.: A low temperature processable ternary gallium alloy for via filling application in microelectronic packaging. J. Mater. Sci. - Mater. Electron. 11(9), 653656 (2000).CrossRefGoogle Scholar
22.Chen, K.I. and Lin, K.L.: The microstructures and mechanical properties of the Sn-Zn-Ag-Al-Ga solder alloys-the effect of Ga. J. Electron. Mater. 32(10), 11111116 (2003).CrossRefGoogle Scholar
23.Chen, W.X., Xue, S.B., and Wang, H.: Wetting properties and interfacial microstructures of Sn-Zn-xGa solders on Cu substrate. Mater. Des. 31(4), 21962200 (2010).CrossRefGoogle Scholar
24.Chen, W.X., Xue, S.B., Wang, H., Wang, J.X., and Han, Z.J.: Investigation on properties of Ga to Sn-9Zn lead-free solder. J. Mater. Sci. - Mater. Electron. 21(5), 496502 (2010).CrossRefGoogle Scholar
25.Zhang, Y., Liang, T.X., and Jusheng, M.A: Phase diagram calculation on Sn-Zn-Ga solders. J. Non-Cryst. Solids 336(2), 153156 (2004).CrossRefGoogle Scholar
26.Chen, K.I., Cheng, S.C., Wu, S., and Lin, K.L.: Effects of small additions of Ag, Al, and Ga on the structure and properties of the Sn-9Zn eutectic alloy. J. Alloys Compd. 416(2), 98105 (2006).CrossRefGoogle Scholar
27.Choi, J.O., Kim, J.Y., Choi, C.O., Kim, J.K., and Rohatgi, P.K.: Effect of rare earth element on microstructure formation and mechanical properties of thin wall ductile iron castings. Mater. Sci. Eng., A 383(2), 323333 (2004).CrossRefGoogle Scholar
28.Li, Y. and Jones, H.: Effect of rare earth and silicon additions on structure and properties of melt spun Mg-9Al-1Zn alloy. Mater. Sci. Technol. 12(8), 9811070 (1996).Google Scholar
29.Golmakaniyoon, S. and Mahmudi, R.: Microstructure and creep behavior of the rare-earth doped Mg-6Zn-3Cu cast alloy. Mater. Sci. Eng., A 528(3), 16681677 (2011).CrossRefGoogle Scholar
30.Wu, C.M.L. and Wong, Y.W.: Rare-earth additions to lead-free electronic solders. J. Mater. Sci - Mater. Electron. 18(1–3), 7791 (2007).CrossRefGoogle Scholar
31.Wu, C.M.L., Yu, D.Q., Law, C.M.T., and Wang, L.: Properties of lead-free solder alloys with rare earth element additions. Mater. Sci. Eng., R 44(1), 144 (2004).CrossRefGoogle Scholar
32.Wu, C.M.L., Yu, D.Q., Law, C.M.T., and Wang, L.: The properties of Sn-9Zn lead-free solder alloys doped with trace rare earth elements. J. Electron. Mater. 31(9), 921927 (2002).CrossRefGoogle Scholar
33.Wu, C.M.L., Law, C.M.T., Yu, D.Q., and Wang, L.: The wettability and microstructure of Sn-Zn-RE alloys. J. Electron. Mater. 32(2), 6399 (2003).CrossRefGoogle Scholar
34.Dudek, M.A., Sidhu, R.S., and Chawla, N.: Novel rare-earth-containing lead-free solders with enhanced ductility. JOM 58(6), 5762 (2006).CrossRefGoogle Scholar
35.Dudek, M.A., Sidhu, R.S., Chawla, N., and Renavikar, M.: Microstructure and mechanical behavior of novel rare earth-containing Pb-Free solders. J. Electron. Mater. 35(12), 20882097 (2006).CrossRefGoogle Scholar
36.Zeng, G., Xue, S.B., Zhang, L., Gao, L.L., Lai, Z.M., and Luo, J.D.: Properties microstructure Sn-0.7Cu-0.05Ni solder bearing rare earth element Pr. J. Mater. Sci. - Mater. Electron. 22(8), 11011108 (2011).CrossRefGoogle Scholar
37.Dudek, M.A. and Chawla, N.: Effect of rare earth (La, Ce, and Y) additions on the microstructure and mechanical behavior of Sn-3.9Ag-0.7Cu solder alloy. Metall. Mater. Trans. A 41(3), 610620 (2010).CrossRefGoogle Scholar
38.Dudek, M.A. and Chawla, N.: Mechanisms of Sn whisker growth in rare-earth (RE) containing Pb-free solders. Acta Mater. 57(15), 45884599 (2009).CrossRefGoogle Scholar
39.Dudek, M.A. and Chawla, N.: Nanoindentation of rare earth-Sn intermetallics in Pb-free solders. Intermetallics 18(5), 10161020 (2010).CrossRefGoogle Scholar
40.Hao, H., Shi, Y.W., Xia, Z.D., Leiand, Y.P., and Guo, F.: Oxidization-induced tin whisker growth on the surface of Sn-3.8Ag-0.7Cu-1.0Er alloy. Metall. Mater. Trans. A 40(8), 20162021 (2009).CrossRefGoogle Scholar
41.Baker, H. and Okamoto, H.: Alloy Phase Diagrams (ASME International, ASM Handbook, 1992).Google Scholar
42.Ye, H., Xue, S.B., Zhang, L., Xiao, Z.X., Hu, Y.H., Lai, Z.M., and Zhu, H.: Sn whisker growth in Sn-9Zn-0.5Ga-0.7Pr lead-free solder. J. Alloys Compd. 509(5), 5255 (2011).CrossRefGoogle Scholar
43.Nychka, J.A., Li, Y., Yangand, F.Q., and Chen, R.: Can whiskers grow on bulk lead-free solder? J. Electron. Mater. 1, 9095 (2008).CrossRefGoogle Scholar
44.Tu, K.N. and Li, J.C.M.: Spontaneous whisker growth on lead-free solder finishes. Mater. Sci. Eng., A 409(2), 131139 (2005).CrossRefGoogle Scholar
45.Speight, J.G.: Lange’s Handbook of Chemistry, 16th ed. (McGraw-Hill, New York, 2005).Google Scholar
46.Dudek, M.A. and Chawla, N.: Oxidation behavior of rare-earth containing Sn-rich solders. J. Electron. Mater. 38(2), 210220 (2009).CrossRefGoogle Scholar
47.Ellis, W.C. and Gibbons, D.F.: Growth and perfection of crystals, edited by Treuting, R.C., Doremus, R.H., Roberts, B.W., and Turnbull, D. (John Wiley, New York, 1958).Google Scholar