TEM Study of Bi Segregation in the Interconnect of Eutectic Tin-Bismuth Solder and Copper

Author

Shang, P.J. ; Liu, Z.Q. ; Zhang, L. ; Li, D.X. ; Shang, J.K.

Author_Institution

Chinese Acad. of Sci., Shenyang

fYear

2007

fDate

14-17 Aug. 2007

Firstpage

1

Lastpage

4

Abstract

The interfacial reaction between eutectic SnBi and Cu was studied by TEM after the sample was reflowed and aged in solid state, respectively. The microstructural evolution at the SnBi/Cu interface during reflowed and solid-state aged process was analyzed. The results show that there are two layers of intermetallic compounds (IMCs), Cu₃Sn and Cu₆Sn₅, located at the interface between solder and Cu after the sample was reflowed. The segregation of Bi at the interface between Cu₃Sn and Cu was observed. Furthermore, the segregation of Bi induced the formation of voids at Cu₃Sn/Cu interface during solid-state aging process.

Keywords

ageing; bismuth alloys; copper; eutectic alloys; interconnections; reflow soldering; surface segregation; tin alloys; transmission electron microscopy; voids (solid); Cu₃Sn; Cu₆Sn₅; SnBi-Cu; TEM study; bismuth segregation; copper; electronic interconnection; eutectic tin-bismuth solder; interfacial reaction; intermetallic compounds; microstructural evolution; reflowing process; solid-state aging process; void formation; Aging; Bismuth; Copper; Environmentally friendly manufacturing techniques; Integrated circuit interconnections; Intermetallic; Lead; Materials science and technology; Soldering; Solid state circuits;

fLanguage

English

Publisher

ieee

Conference_Titel

Electronic Packaging Technology, 2007. ICEPT 2007. 8th International Conference on

Conference_Location

Shanghai

Print_ISBN

978-1-4244-1392-8

Electronic_ISBN

978-1-4244-1392-8

Type

conf

DOI

10.1109/ICEPT.2007.4441534

Filename

4441534