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Metallurgical reactions of Sn-3.5Ag solder with various thicknesses of electroplated Ni/Cu under bump metallization

Published online by Cambridge University Press:  03 March 2011

Chang Pin Huang ,
Chih Chen ,
C.Y. Liu ,
S.S. Lin  and
K.H. Chen
Chang Pin Huang
Affiliation:
Department of Material Science and Engineering, National Chiao Tung University, Hsinchu 30050, Taiwan, Republic of China
Chih Chen*
Affiliation:
Department of Material Science and Engineering, National Chiao Tung University, Hsinchu 30050, Taiwan, Republic of China
C.Y. Liu
Affiliation:
Department of Chemical Engineering and Materials Engineering, National Central University, Chung-Li, Taiwan, Republic of China
S.S. Lin
Affiliation:
Megic Corporation, Ltd., Hsin-chu 300, Taiwan, Republic of China
K.H. Chen
Affiliation:
Megic Corporation, Ltd., Hsin-chu 300, Taiwan, Republic of China
*
a)Address all correspondence to this author. e-mail: chih@cc.nctu.edu.tw
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Abstract

Nickel has been widely used as an under-bump metallization (UBM) material in the microelectronics industry. The solid-state reaction between the eutectic SnAg solder bumps and three thicknesses of Ni/Cu UBM was investigated, with 5 μm-Cu/3 μm-Ni, 3 μm-Cu/2 μm-Ni, and 0 μm-Cu/1 μm-Ni. It was found that the shear strength of the solder bumps decreased after the solid-state aging at 150 °C for 200 h, and it did not change much after it was prolonged for 500 and 1000 h. Aging of the Ag3Sn intermetallic compound (IMC) and grain growth of the solder are responsible for the decrease in the shear strength. Furthermore, the shear test results indicated that the fracture mode switched from ductile to brittle for the solder bumps with 1 μm Ni after aging longer than 200 h, causing the strength of the solder to decrease abruptly. This is attributed to the consumption of the peripheral Ni layer after the solid-state aging for 1000 h. The Ni consumption rate was measured to be 0.02 μm/h1/2 at 150 °C.

Keywords

DiffusionPackaging
Type
Articles
Information
Journal of Materials Research , Volume 20 , Issue 10 , October 2005 , pp. 2772 - 2779
Copyright
Copyright © Materials Research Society 2005

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References

REFERENCES

1Lau, J.H.: Flip Chip Technology (McGraw-Hill, New York, 1995), Chap. 3, p. 123.Google Scholar
2Miller, L.F.: Controlled collapse reflow chip jointing. IBM J. Res. Develop. 13(3), 239 (1969).CrossRefGoogle Scholar
3Totta, P.A. and Sopher, R.P.: SLT device metallurgy and its monolithic extension. IBM J. Res. Develop. 13(3), 226 (1969).CrossRefGoogle Scholar
4Suraski, D. and Seelig, K.: The current status of lead-free solder alloys. IEEE Trans. Electron. Pack. Manuf., 24, 244 (2001).CrossRefGoogle Scholar
5Tu, K.N. and Zeng, K.: Sn-Pb solder reaction in flip chip technology. Mater. Sci. Eng. Rep. R 34, 1 (2001).CrossRefGoogle Scholar
6Kim, H.K. and Tu, K.N.: Rate of consumption of Cu soldering accompanied by ripening. Appl. Phys. Lett. 67, 2002 (1995).CrossRefGoogle Scholar
7Liu, A.A., Kim, H.K., Tu, K.N. and Totta, P.A.: Palling of Cu6Sn5 spheroids in the soldering reaction of eutectic SnPb on Cr/Cu/Au thin films. J. Appl. Phys. 80, 2774 (1996).CrossRefGoogle Scholar
8Kim, P.G., Jang, J.W., Lee, T.Y. and Tu, K.N.: Interfacial reaction and wetting behavior in eutectic SnPb solder on Ni/Ti thin films and Ni foils. J. Appl. Phys. 86, 6746 (1999).CrossRefGoogle Scholar
9Liu, C.Y., Tu, K.N., Sheng, T.T., Tung, C.H., Frear, D.R. and Elenius, P.: Electron microscopy study of interfacial reaction between eutectic SnPb and Cu/Ni(V)/Al thin film metallization. J. Appl. Phys. 87, 750 (2000).CrossRefGoogle Scholar
10Kim, S.H., Kim, J.Y., Yu, J. and Lee, T.Y.: Residual stress and interfacial reaction of the electroplated Ni-Cu alloy under bump metallurgy in the flip-chip solder joint. J. Electron. Mater. 33, 948 (2004).CrossRefGoogle Scholar
11Korhonen, T.M., Su, P., Hong, S.J., Korhonen, M.A. and Li, C.Y.: Reactions of lead-free solders with CuNi metallizations. J. Electron. Mater. 29, 1194 (2000).CrossRefGoogle Scholar
12Duan, L.L., Yu, D.Q., Han, S.Q., Zhao, J., and Wang, L.: Microstructure and interface reaction between Sn-3.5Ag solder and electroplated Ni layer on Cu substrate during high temperature exposure, in Business of Electronic Product Reliability and Liability, 2004 International Conference on Apr 27–30, (IEEE, Shanghai, China, 2004), pp. 35–41.Google Scholar
13Zeng, K. and Tu, K.N.: Six cases of reliability study of Pb-free solder joints in electronic packaging technology. Mater. Sci. Eng. R 38, 55 (2002).CrossRefGoogle Scholar
14Chan, Y.C., Tu, P.L., Tang, C.W., Hung, K.C., and Lai, J.K.L.: Reliability studies of μBGA solder joints-effect of Ni–Sn intermetallic compound. IEEE Trans. Adv. Pack. 24, 25 (2001).CrossRefGoogle Scholar
15Huang, C.S., Duh, J.G. and Chen, Y.M.: Metallurgical reaction of the Sn–3.5Ag solder and Sn–37Pb solder with Ni/Cu under-bump metallization in a flip-chip package. J. Electron. Mater. 32, 1509 (2003).CrossRefGoogle Scholar
16Ochoa, F., Williams, J.J. and Chawla, N.: Effects of cooling rate on the microstructure and tensile behavior of a Sn–3.5 wt% Ag solder. J. Electron. Mater. 32, 1414 (2003).CrossRefGoogle Scholar
17Lee, H.T., Chen, M.H., Jao, H.M. and Hsu, C.J.: Effect of adding Sb on microstructure and adhesive strength of Sn–Ag solder joint. J. Electron. Mater. 33, 1048 (2004).CrossRefGoogle Scholar
18Sharif, A., Islam, M.N. and Chan, C.Y.: Interfacial reactions of BGA Sn–3.5% Ag–0.5% Cu and Sn–3.5% Ag solder during high-temperature aging with Ni/Au metallization. Mater. Sci. Eng. B 113, 184 (2004).CrossRefGoogle Scholar
19Peng, C.T., Kuo, C.T., and Chiang, K.N.: Experimental characterization and mechanical behavior analysis on intermetallic compounds of 96.5Sn–3.5Ag and 63Sn–37Pb solder bump with Ti–Cu–Ni UBM on copper chip, in Electronic Components and Technology Conference, (IEEE, Las Vegas, NV, 2004), Vol. 1, pp. 90–97.Google Scholar
20Gusak, A.M. and Tu, K.N.: Theory of normal grain growth in normalized size space. Acta Mater. 51, 3895 (2003).CrossRefGoogle Scholar
21Reed-Hill, R.E. and Abbaschian, R.: Physical Metallurgy Principles, 3rd ed. (Florida Univ. Press, PWS Publishing Company, Boston, MA, 1994), pp. 185, 251.Google Scholar
22Reed-Hill, R.E. and Abbaschian, R.: Physical Metallurgy Principles, 3rd ed. (PWS Publishing Company, Boston, MA, 1994), p. 193.Google Scholar
23Gusak, A.M. and Tu, K.N.: Kinetic theory of flux-driven ripening. Phys. Rev. B 66, 115403 (2002).CrossRefGoogle Scholar
24Reed-Hill, R.E. and Abbaschian, R.: Physical Metallurgy Principles, 3rd ed. (PWS Publishing company, Boston, MA, 1994), pp. 118, 120, 532.Google Scholar