Journal of Electronic Materials

, Volume 36, Issue 10, pp 1372–1377 | Cite as

Current-Induced Phase Partitioning in Eutectic Indium-Tin Pb-Free Solder Interconnect

Open Access

Structural changes from high-density electric currents were examined in a eutectic In-Sn/Cu interconnect. Under electrical loading, Sn and In migrated in opposite directions, creating a partition of the Sn- and In-rich phases between the anode and the cathode. At the anode, a net gain of Sn atoms resulted in the formation of massive, columnar hillocks on the surface, but a net loss of In led to dissolution and disappearance of the In-rich intermetallic layer. At the cathode, the exodus of Sn left valleys adjacent to the In-rich regions on the surface, while the amount of the In-rich phase grew, due to the net influx of In at the expense of the In-rich intermetallic layer.

Key words

In-Sn solder electromigration current stressing hillocks interface 



Support for this study was provided by the Chinese Natural Sciences Foundation, grant # 50228101, and the National Basic Research Program of China, grant # 2004CB619306. The authors also owe special thanks to Dr. Warke, Q.L. Yang and others in the Microelectronics Laboratory at IMR for their assistance.


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Copyright information

© TMS 2007

Authors and Affiliations

  1. 1.Shenyang National Laboratory for Materials Science, Institute of Metals ResearchCASShenyangChina
  2. 2.Department of Materials Science and EngineeringUniversity of Illinois at Urbana-ChampaignUrbanaUSA

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