Hostname: page-component-848d4c4894-xfwgj Total loading time: 0 Render date: 2024-07-06T18:24:05.919Z Has data issue: false hasContentIssue false
  • English
  • Français

Transition of Bi embrittlement of SnBi/Cu joint couples with reflow temperature

Published online by Cambridge University Press:  17 January 2011

H.F. Zou ,
Q.K. Zhang  and
Z.F. Zhang
H.F. Zou
Affiliation:
Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, People’s Republic of China
Q.K. Zhang
Affiliation:
Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, People’s Republic of China
Z.F. Zhang*
Affiliation:
Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, People’s Republic of China
*
a)Address all correspondence to this author. e-mail: zhfzhang@imr.ac.cn
Get access

Abstract

The current study revealed the effects of reflow temperature and the reflow time on the interfacial embrittlement of SnBi/Cu joints. When the reflow temperature is below 220 °C, the joints reflowed for 150 min often fail in brittle mode because the Bi atoms from the SnBi solder easily segregated at the Cu3Sn/Cu interface. In contrast, Bi embrittlement did not occur for joints reflowed at above 260 °C for 150 min because the Bi particles were frozen in the Cu3Sn layer during the formation of intermetallic compounds (IMC) at the initial reflow stage, mainly located at the Cu3Sn grain boundary. It is interesting to note that the Bi embrittlement did occur when the joints were reflowed at above 260 °C for 250 min, which should be attributed to Bi diffusion. It is concluded that the Bi particles are frozen in the Cu3Sn layer with increasing reflow temperature, that cannot eliminate Bi embrittlement, and can only delay the occurrence of Bi embrittlement.

Type
Articles
Information
Journal of Materials Research , Volume 26 , Issue 3 , 14 February 2011 , pp. 449 - 454
Copyright
Copyright © Materials Research Society 2011

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.Liu, P.L. and Shang, J.K.: Interfacial segregation of bismuth in copper/tin-bismuth solder interconnect. Scr. Mater. 44, 1019 (2001).Google Scholar
2.Liu, P.L. and Shang, J.K.: Fracture of SnBi/Ni(P) interfaces. J. Mater. Res. 20, 818 (2005).Google Scholar
3.Zhu, Q.S., Zhang, Z.F., Wang, Z.G., and Shang, J.K.: Inhibition of interfacial embrittlement at SnBi/Cu single crystal by electrodeposited Ag film. J. Mater. Res. 23, 78 (2008).Google Scholar
4.Zou, H.F., Zhang, Q.K., and Zhang, Z.F.: Eliminating interfacial segregation and embrittlement of bismuth in SnBi/Cu joint by alloying Cu substrate. Scr. Mater. 61, 308 (2009).Google Scholar
5.Zhang, Q.K., Zou, H.F., and Zhang, Z.F.: Improving tensile and fatigue properties of Sn-58Bi/Cu solder joints through alloying substrate. J. Mater. Res. 25, 303 (2010).CrossRefGoogle Scholar
6.IPMA: The Thermodynamic Databank for Interconnection and Packaging Materials (Helsinki University of Technology, Helsinki, 2000).Google Scholar
7.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).Google Scholar
8.Keene, B.J.: Review of data for the surface tension of pure metals. Int. Mater. Rev. 38, 157 (1993).Google Scholar
9.Zou, H.F., Zhu, Q.S., and Zhang, Z.F.: Growth kinetics of intermetallic compounds and tensile properties of Sn-Ag-Cu/Ag single crystal joint. J. Alloys Compd. 461, 410 (2008).Google Scholar
10.Wu, B.Y., Zhong, H.W., Chan, Y.C., and Alam, M.O.: Shearing tests of solder joints on tape ball grid array substrates. J. Mater. Res. 21, 2224 (2006).CrossRefGoogle Scholar
11.Liu, P.L. and Shang, J.K.: Interfacial embrittlement by bismuth segregation in copper/tin-bismuth Pb-free solder interconnect. J. Mater. Res. 16, 1651 (2001).CrossRefGoogle Scholar
12.Shang, P.J., Liu, Z.Q., Li, D.X., and Shang, J.K.: Bi-induced voids at the Cu3Sn/Cu interface in eutectic SnBi/Cu solder joints. Scr. Mater. 58, 409 (2008).CrossRefGoogle Scholar
13.Zeng, 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 (2005).Google Scholar
14.Tu, K.N.: Solder Joint Technology Materials, Properties and Reliability (Springer, New York, 2007).CrossRefGoogle Scholar