Hostname: page-component-5cf477f64f-fcbfl Total loading time: 0 Render date: 2025-04-07T08:11:36.969Z Has data issue: false hasContentIssue false
  • English
  • Français

Interfacial embrittlement by bismuth segregation in copper/tin–bismuth Pb-free solder interconnect

Published online by Cambridge University Press:  31 January 2011

P. L. Liu  and
J. K. Shang
P. L. Liu
Affiliation:
Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801
J. K. Shang
Affiliation:
Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801
Get access

Abstract

Microchemistry and mechanical properties of a copper/tin–bismuth Pb-free solder interconnect were examined in the as-reflowed and aged conditions by in situ Auger fracture and interface fracture mechanics techniques. In the as-reflowed condition, the solder–copper interface was highly resistant to fracture, and the fracture mechanism was ductile with the crack path following the interface between the solder alloy and the copper–tin intermetallic phase. Upon thermal aging, bismuth segregation was found to occur on the copper–intermetallic interface. Auger depth profiling indicated that the segregation was confined to about one monolayer from the interface. The segregation was shown to embrittle the interface, resulting in an approximately 5-fold decrease in the interfacial fracture resistance.

Type
Articles
Information
Journal of Materials Research , Volume 16 , Issue 6 , June 2001 , pp. 1651 - 1659
Copyright
Copyright © Materials Research Society 2001

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1.Mei, Z.C., Hua, F., and Glazer, J., in Proceedings of SMTA Inter-national, (SMTA International, Edina, MN, 1999), p. 399.Google Scholar
2.Lee, N C., Adv. Microelectr. 26, 29 (1999).Google Scholar
3.Hua, F., Mei, Z., and Glazer, J., in Proceedings of 48th Electronic Components and Technology Conference, (IEEE, New York, 1998), p. 277.Google Scholar
4.Lee, N.C., Solder. Surf. Mount Technol. 9, 65 (1997).CrossRefGoogle Scholar
5.Yamagishi, Y., Ochiai, M., Ueda, H., Nakanishi, T., and Kitazima, M., in Proceedings of the 9th International Microelectronics Confer-ence, (ISHM, Tokyo, Japan, 1996) p. 252.Google Scholar
6.Glazer, J., Int. Mater. Rev. 40, 65 (1995).CrossRefGoogle Scholar
7.Mei, Z. and Morris, J.W. Jr., J. Electron. Mater. 21, 599 (1992).CrossRefGoogle Scholar
8.Tomlinson, W.J. and Collier, I.J., J. Mater. Sci. 22, 1835 (1987).CrossRefGoogle Scholar
9.Frear, D.R. and Vianco, P.T., Metall. Mater. Trans. 25A, 1509 (1994).CrossRefGoogle Scholar
10.Sunwoo, A.J., Morris, J.W. Jr., and Lucey, G.K. Jr., Metall. Mater. Trans. 23A, 1323 (1992).CrossRefGoogle Scholar
11.Yao, D. and Shang, J.K., Metall. Mater. Trans. 26A, 2677 (1995).CrossRefGoogle Scholar
12.Vianco, P.T., Erickson, K.L., and Hopkins, P.L., J. Electron. Mater. 23, 721 (1994).CrossRefGoogle Scholar
13.Felton, L.E., Raeder, C.H., and Knorr, D.B., J. Met. 45, 28 (1993).Google Scholar
14.Vianco, P.T., Kilgo, A.C., and Grant, R., J. Electron. Mater. 24, 1493 (1995).CrossRefGoogle Scholar
15.Powell, B.D. and Mykura, H., Acta Mater. 21, 1151 (1973).CrossRefGoogle Scholar
16.Chang, L.S., Rabkin, E., Straumal, B.B., Baretzky, B., and Gust, W., Acta Mater. 47, 4041 (1999).CrossRefGoogle Scholar
17.Michael, J.R. and Williams, D.B., Metall. Mater. Trans. A 15A, 99 (1984).CrossRefGoogle Scholar
18.Menyhard, M., Blum, B., and McMahon, C.J. Jr., Acta Mater. 37, 549 (1989).CrossRefGoogle Scholar
19.Zhou, F.X., Peng, B.Y., and Wu, X.J., J. Appl. Phys. 68, 548 (1990).CrossRefGoogle Scholar
20.Luzzi, D.E., Yan, M., Sob, M., and Vitek, V., Phys. Rev. Lett. 67, 1894 (1991).CrossRefGoogle Scholar
21.Yan, M., Sob, M., Luzzi, D.E., and Vitek, V., Phys. Rev. B 47, 5571 (1993).CrossRefGoogle Scholar
22.Chang, L.S., Rabkin, E., Baretzky, B., and Gust, W., Scripta Mater. 38, 1033 (1998).CrossRefGoogle Scholar
23.Alber, U., Mullejans, H., and Ruhle, M., Acta Mater. 47, 4047 (1999).CrossRefGoogle Scholar
24.Chang, L.S., Rabkin, E., Hofmann, S., and Gust, W., Acta Mater. 47, 2951 (1999).CrossRefGoogle Scholar
25.Zhang, Z. and Shang, J.K., Metall. Mater. Trans. A 27A, 205 (1996).CrossRefGoogle Scholar
26.Zhang, Z., Ph.D. Thesis, University of Illinois at Urbana-Champaign, Urbana, Illinois (1997).Google Scholar
27.Liu, P.L. and Shang, J.K., J. Electron. Mater. 29, 622 (2000).CrossRefGoogle Scholar
28.Liu, P.L. and Shang, J.K., Metall. Mater. Trans. A 31A, 286 (2000).Google Scholar
29.Ritchie, R.O., Int. Metals Rev. 20, 205 (1979).Google Scholar
30.Tribula, D. and Morris, J.W. Jr., J. Electron. Packaging 112, 87 (1990).CrossRefGoogle Scholar
31.Kramer, P.A., Glazer, J., and Morris, J.W. Jr., Metall. Mater. Trans. 25A, 1249 (1995).Google Scholar
32.Frear, D.R., Hosking, F.M., and Vianco, P.T., in Materials Developments in Microelectronic Packaging Conference Proceedings, (Montreal, Quebec, Canada, 1991), p. 229.Google Scholar