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Interfacial reactions of Sn-Cu/Ni couples at 250 °C

Published online by Cambridge University Press:  03 March 2011

Sinn-wen Chen*
Affiliation:
Department of Chemical Engineering, National Tsing Hua University, Hsin-Chu, Taiwan 300
Chao-hong Wang
Affiliation:
Department of Chemical Engineering, National Tsing Hua University, Hsin-Chu, Taiwan 300
*
a) Address all correspondence to this author. e-mail: [email protected]
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Abstract

Interfacial reactions of Sn-Cu alloys with Ni substrate at 250 °C have been investigated by varying the Cu contents from 0.3wt%Cu to 3.0wt%Cu. The Cu6Sn5 phase is not found in the Sn-0.3wt%Cu/Ni couple. The interfacial reaction sequence of the Sn-0.6wt%Cu/Ni couple is similar to that of the Sn-0.7wt%Cu/Ni. The reaction follows Cu6Sn5 formation stage, growth stage, detachment stage, Cu6Sn5 layer continuing growth stage, Ni3Sn4 formation stage, Cu6Sn5 phase dissolution stage, Ni3Sn4 detachment stage, and Ni3Sn4 phase dissolution stage. Similar results are found for the couples prepared with higher Cu contents, 0.8wt%Cu, 1.0wt%Cu, 2.0wt%Cu, and 3.0wt%Cu, but the detachment positions are different. For the couples with higher Cu-content, the layer detaches at the Cu6Sn5/Ni interface; however, for the 0.6wt%Cu and 0.7wt%Cu couples, the Cu6Sn5 phase layer fractures and detachment occurs inside the layer. Morphologies of the Cu6Sn5 phase are also found to change with Cu contents: the pyramidal shape in the 0.3wt%Cu couple changes to the rod-shape in the 0.8wt%Cu couple, and becomes a very fine rod shape in the 2.0wt%Cu couple.

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Copyright © Materials Research Society 2006

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References

REFERENCES

1Choi, S., Bieler, T.R., Lucas, J.P., and Subramanian, K.N.: Characterization of the growth of intermetallic interfacial layers of Sn-Ag and Sn-Pb eutectic solders and their composite solders on Cu substrate during isothermal long-term aging. J. Electron. Mater. 28, 1209 (1999).CrossRefGoogle Scholar
2Tu, K.N., Gusak, A.M., and Li, M.: Physics and materials challenges for lead-free solders. J. Appl. Phys. 93, 1335 (2003).CrossRefGoogle Scholar
3Frear, D.R., Jang, J.W., Lin, J.K., and Zhang, C.: Pb-free solders for flip chip interconnects. JOM 53, 28 (2001).CrossRefGoogle Scholar
4Abtew, M. and Selvaduray, G.: Lead-free solders in microelectronics. Mater. Sci. Eng. R27, 95 (2000).CrossRefGoogle Scholar
5Glazer, J.: Metallurgy of low temperature Pb-free solders for electronic assembly. Int. Mater. Rev. 40, 63 (1995).CrossRefGoogle Scholar
6Zhang, F., Li, M., Chum, C.C., and Tu, K.N.: Influence of substrate metallization on diffusion and reaction at the under-bump metallization/solder interface in flip-chip packages. J. Mater. Res. 17, 2757 (2002).CrossRefGoogle Scholar
7Chen, W.T., Ho, C.E., and Kao, C.R.: Effect of Cu concentration on the interfacial reactions between Ni and Sn-Cu solders. J. Mater. Res. 17, 263 (2002).CrossRefGoogle Scholar
8Lin, C-H., Chen, S-W., and Wang, C-H.: Phase equilibria and solidification properties of Sn-Cu-Ni alloys. J. Electron. Mater. 31, 907 (2002).CrossRefGoogle Scholar
9Chen, W.T.: Effects of Cu concentration on the interfacial reactions between Ni and Sn-Cu solders. Master Thesis, National Central University, Chungli, Taiwan, (2002).Google Scholar
10Ho, C.E., Tsai, R.Y., Lin, Y.L., and Kao, C.R.: Effect of Cu concentration on the reactions between Sn-Ag-Cu solders and Ni. J. Electron. Mater. 31, 584 (2002).CrossRefGoogle Scholar
11Kim, K.S., Huh, S.H., and Suganuma, K.: Effects of intermetallic compounds on properties of Sn-Ag-Cu lead-free soldered joints. J. Alloys Compd. 352, 226 (2003).CrossRefGoogle Scholar
12Yoon, J.W., Kim, S.W., and Jung, S.B.: IMC morphology, interfacial reaction and joint reliability of Pb-free Sn-Ag-Cu solder on electrolytic Ni BGA substrate. J. Alloys Compd. 392, 247 (2005).CrossRefGoogle Scholar
13Hsu, H-F. and Chen, S-W.: Phase equilibria of the Sn-Ag-Ni ternary system and interfacial reactions at the Sn-Ag-Ni joints. Acta Mater. 52, 2541 (2004).CrossRefGoogle Scholar
14Yu, D.Q., Wu, C.M.L., He, D.P., Zhao, N., Wang, L., and Lai, J.K.L.: Effects of Cu contents in Sn-Cu solder on the composition and morphology of intermetallic compounds at a solder/Ni interface. J. Mater. Res. 20, 2205 (2005).CrossRefGoogle Scholar
15Wang, C-H. and Chen, S-W.: Sn-0.7wt%Cu/Ni interfacial reactions at 250 °C. Acta Mater. 54, 247 (2006).CrossRefGoogle Scholar
16Lu, H.Y., Balkan, H., and Ng, K.Y.S.: Solid-liquid reactions: The effect of Cu content on Sn-Ag-Cu interconnects. JOM 57, 30 (2002).CrossRefGoogle Scholar
17Chen, S-W. and Chang, C.A.: Phase equilibra of the Sn-Ag-Cu-Ni quaternary system at the Sn-rich corner. J. Electron. Mater. 33, 1071 (2004).CrossRefGoogle Scholar