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Cruciform pattern formation in Sn/Co couples

Published online by Cambridge University Press:  31 January 2011

Chao-hong Wang  and
Sinn-wen Chen
Chao-hong Wang
Affiliation:
Department of Chemical Engineering, National Tsing Hua University, Hsin-chu, Taiwan 300
Sinn-wen Chen
Affiliation:
Department of Chemical Engineering, National Tsing Hua University, Hsin-chu, Taiwan 300
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Abstract

CoSn3 phase is formed in Sn/Co couples reacted at 200 °C. The reaction phase shows a unique cruciform pattern that is observed for the first time in the solid/solid reaction. The reaction phase layers are thick and uniform along the edges of the Co substrate, and there are no reaction phases at the corners. A continuous reaction layer is formed in Sn/Co couples reacted at 180 °C. A metastable CoSn4 phase is formed at the corner, and the reaction phase along the edge of the Co substrate is the CoSn3 phase. The reaction CoSn3 phase region shows a cruciform pattern if the CoSn4 phase region is ignored. It is concluded that the Sn flux is much faster than the Co flux, and the cruciform pattern of the reaction CoSn3 phase layer is formed either by cracking or transformation to the CoSn4 phase at the corners where stresses are most intensified.

Keywords

MicrostructureSolderingSn
Type
Articles
Information
Journal of Materials Research , Volume 22 , Issue 12 , December 2007 , pp. 3404 - 3409
Copyright
Copyright © Materials Research Society 2007

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References

REFERENCES

1Sun, P., Anderson, C., Wei, X., Cheng, Z., Shangguan, D.Liu, J.: Intermetallic compound formation in Sn–Co–Cu, Sn–Ag–Cu and eutectic Sn–Cu solder joints on electroless Ni(P) immersion Au surface finish after reflow soldering. Mater. Sci. Eng., B 135, 134 2006CrossRefGoogle Scholar
2Magagnin, L., Sirtori, V., Seregni, S., Origo, A.Cavallotti, P.L.: Electroless Co–P for diffusion barrier in Pb-free soldering. Electrochim. Acta 50, 4621 2005CrossRefGoogle Scholar
3Ratchev, P., Labie, R.Beyne, E.: Nanohardness study of CoSn2 intermetallic layers formed between Co-UBM and Sn flip chip solder joints,Proceedings 2004 EPTC Conference,2004 339Google Scholar
4Labie, R., Beybe, E.Ratchev, P.: Investigation of Co UBM for direct bumping on Cu/low K dies. Proceedings 2003 ECTC Conference,,2003 1230Google Scholar
5Yamamoto, T., Sakatani, S., Kobayashi, S., Uenishi, K., Kobayashi, K., Ishio, M., Shiomi, K., Hashimoto, A.Yamamoto, M.: Reactivity between Sn–Ag solder and Au/Ni–Co plating to form intermetallic phases. Mater. Trans. 46, 2406 2005CrossRefGoogle Scholar
6Chao, Y-H.Chen, S-W.: unpublished results, 2007Google Scholar
7Scheil, E.: The appearance of a high power of crystallization in the formation of iron–zinc alloys. Z. Metallkd. 27, 76 1935Google Scholar
8Mackowiak, J.Shreir, L.L.: The nature and growth of interaction layers formed during the reaction between solid titanium and liquid aluminium. J. Less-Common Met. 1, 456 1959CrossRefGoogle Scholar
9Barbier, F.Blanc, J.: Corrosion of martensitic and austenitic steels in liquid gallium. J. Mater. Res. 14, 737 1999CrossRefGoogle Scholar
10Xu, Q., Zhang, H., Ding, B.Hu, Z.: Nature and growth of interaction layers formed during the reaction between solid Ni and liquid Al. J. Mater. Sci. Technol. 18, 512 2002Google Scholar
11Chen, S-W.Chiu, C-N.: Unusual cruciform pattern interfacial reactions in Sn/Te couples. Scripta Mater. 56, 97 2007CrossRefGoogle Scholar
12Chiu, C-N., Wang, C-H.Chen, S-W.: Interfacial reactions in the Sn–Bi/Te couples. J. Electron. Mater.,, DOI: 10.1007/s11664-007-0264-8, (2007, accepted for publication)CrossRefGoogle Scholar
13Lang, A.Jeitschko, W.: Two new phases in the system cobalt– tin: The crystal structures of alpha- and beta-CoSn3. Z. Metallkd. 87, 759 1996Google Scholar
14Jiang, M., Sato, J., Ohnuma, I., Kainuma, R.Ishida, K.: A thermodynamic assessment of the Co–Sn system. Calphad 28, 213 2004CrossRefGoogle Scholar
15Chang, W-C.: A new surface finish for solder joints exhibiting both low consumption rate and oxidation resistance. Master Thesis, National Central University, Taiwan,,2004Google Scholar
16Ishida, K.Nishizawa, T.: The Co–Sn System. J. Phase Equilib. 12, 88 1991CrossRefGoogle Scholar
17Okamoto, H.: Co–Sn. J. Phase Equilib. Diffus. 27, 308 2006CrossRefGoogle Scholar
18Chen, C-M.Chen, S-W.: Electric current effects on Sn/Ag interfacial reactions. J. Electron. Mater. 28, 902 1999CrossRefGoogle Scholar
19Chen, C-M.Chen, S-W.: Electric current effects upon the Sn/Cu and Sn/Ni interfacial reactions. J. Electron. Mater. 27, 1193 1998CrossRefGoogle Scholar
20Vianco, P.T., Rejent, J.A.Hlava, P.F.: Solid-state intermetallic compound layer growth between copper and 95.5Sn–3.9Ag– 0.6Cu solder. J. Electron. Mater. 33, 991 2004CrossRefGoogle Scholar
21Huang, Y-C., Chen, S-W., Gierlotka, W., Chang, C-H.Wu, J-C.: Dissolution and interfacial reactions of Fe in molten Sn–Cu and Sn–Pb solders. J. Mater. Res. 22(10), 2924 2007CrossRefGoogle Scholar
22Aoyagi, M.: Stress-induced migration model based on atomic migration. J. Mater. Res. 19, 2349 2004CrossRefGoogle Scholar