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Thermal expansion of Cu6Sn5 and (Cu,Ni)6Sn5

Published online by Cambridge University Press:  20 September 2011

Dekui Mu*
Affiliation:
School of Mechanical and Mining Engineering, The University of Queensland, Brisbane, Australia
Jonathan Read
Affiliation:
School of Mechanical and Mining Engineering, The University of Queensland, Brisbane, Australia
Yafeng Yang
Affiliation:
School of Mechanical and Mining Engineering, The University of Queensland, Brisbane, Australia
Kazuhiro Nogita
Affiliation:
School of Mechanical and Mining Engineering, The University of Queensland, Brisbane, Australia
*
a)Address all correspondence to this author. e-mail: [email protected]
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Abstract

Cu6Sn5 is a common intermetallic compound formed during electrical packaging. It has an allotropic transformation from the low-temperature monoclinic η’-Cu6Sn5 to high-temperature hexagonal η-Cu6Sn5 at equilibrium temperature 186 °C. In this research, the effects of this allotropic transformation and Ni addition on the thermal expansion of η’- and/or η-Cu6Sn5 were characterized using synchrotron x-ray diffraction and dilatometry. A volume expansion during the monoclinic to hexagonal transformation was found. The addition of Ni was found to decrease the undesirable thermal expansion by stabilizing the hexagonal Cu6Sn5 at temperatures below 186 °C and reducing the overall thermal expansion of Cu6Sn5.

Type
Articles
Copyright
Copyright © Materials Research Society 2011

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References

REFERENCES

1.Laurila, T., Vuorinen, V., and Kivilahti, J.K.: Interfacial reactions between lead-free solders and common base materials. Mater. Sci. Eng., R 49, 1 (2005).CrossRefGoogle Scholar
2.Chan, Y.C. and Yang, D.: Failure mechanisms of solder interconnect under current stressing in advanced electronic packages. Prog. Mater. Sci. 55, 428 (2010).CrossRefGoogle Scholar
3.Jiang, N., Clum, J.A., Chromik, R.R., and Cotts, E.J.: Thermal expansion of several Sn-based intermetallic compounds. Scr. Mater. 37, 1851 (1997).CrossRefGoogle Scholar
4.Wang, K-K., Gan, D., Hsieh, K-C., and Chiou, S-Y.: The microstructure of η’-Cu6Sn5 and its orientation relationships with Cu in the early stage of growth. Thin Solid Films 518, 1667 (2010).CrossRefGoogle Scholar
5.Zhou, W., Liu, L., and Wu, P.: Structural, electronic and thermo-elastic properties of Cu6Sn5 and Cu5Zn8 intermetallic compounds: First-principles investigation. Intermetallics 18, 922 (2010).CrossRefGoogle Scholar
6.Nogita, K., Gourlay, C.M., and Nishimura, T.: Cracking and phase stability in reaction layers between Sn-Cu-Ni solders and Cu substrates. JOM 61, 45 (2009).CrossRefGoogle Scholar
7.Nogita, K., McDonald, S.D., Tsukamoto, H., Read, J., Suenaga, S., and Nishimura, T.: Inhibiting cracking of interfacial Cu6Sn5 by Ni additions to Sn-based lead-free solders. Trans. Jpn. Inst. Electron. Packag. 2, 46 (2009).CrossRefGoogle Scholar
8.Laurila, T., Hurtig, J., Vuorinen, V., and Kivilahti, J.K.: Effect of Ag, Fe, Au and Ni on the growth kinetics of Sn-Cu intermetallic compound layers. Microelectron. Reliab. 49, 242 (2009).CrossRefGoogle Scholar
9.Gao, F., Takemoto, T., and Nishikawa, H.: Morphology and growth pattern transition of intermetallic compounds between Cu and Sn-3.5 Ag containing a small amount of additives. J. Electron. Mater. 35, 2081 (2006).CrossRefGoogle Scholar
10.Yu, C., Liu, J., Lu, H., Li, P., and Chen, J.: First-principles investigation of the structural and electronic properties of Cu6-xNixSn5 (x= 0, 1, 2) intermetallic compounds. Intermetallics 15, 1471 (2007).CrossRefGoogle Scholar
11.Xu, L. and Pang, J.H.L.: Nano-indentation characterization of Ni-Cu-Sn IMC layer subject to isothermal aging. Thin Solid Films 504, 362 (2006).CrossRefGoogle Scholar
12.Mu, D., Tsukamoto, H., Huang, H., and Nogita, K.: Formation and mechanical properties of intermetallic compounds in Sn-Cu high-temperature lead-free solder joints. Mater. Sci. Forum 654, 2450 (2010).CrossRefGoogle Scholar
13.Larsson, A.K., Stenberg, L., and Lidin, S.: The superstructure of domain-twinned η’-Cu6Sn5. Acta Crystallogr. B 50, 636 (1994).CrossRefGoogle Scholar
14.Nogita, K. and Nishimura, T.: Nickel-stabilized hexagonal (Cu, Ni)6Sn5 in Sn-Cu-Ni lead-free solder alloys. Scr. Mater. 29, 191 (2008).CrossRefGoogle Scholar
15.Nogita, K.: Stabilisation of Cu6Sn5 by Ni in Sn-0.7 Cu-0.05 Ni lead-free solder alloys. Intermetallics 18, 145 (2010).CrossRefGoogle Scholar
16.Schwingenschlögl, U., Di Paola, C., Nogita, K., and Gourlay, C.M.: The influence of Ni additions on the relative stability of η and η’ Cu6Sn5. Appl. Phys. Lett. 96, 061908 (2010).CrossRefGoogle Scholar
17.Izumi, F. and Momma, K.: Three-dimensional visualization in powder diffraction. Solid State Phenom. 130, 15 (2007).CrossRefGoogle Scholar
18.Ghosh, G. and Asta, M.: Phase stability, phase transformations, and elastic properties of Cu6Sn5: Ab initio calculations and experimental results. J. Mater. Res. 20, 3102 (2005).CrossRefGoogle Scholar
19.Zou, H.F., Yang, H.J., and Zhang, Z.F.: Morphologies, orientation relationships and evolution of Cu6Sn5 grains formed between molten Sn and Cu single crystals. Acta Mater. 56, 2649 (2008).CrossRefGoogle Scholar