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A new solder wetting layer for Pb-free solders

Published online by Cambridge University Press:  31 January 2011

Young-Ho Kim*
Affiliation:
Division of Materials Science & Engineering, Hanyang University, Seoul 133-791, Korea
*
a) Address all correspondence to this author. e-mail: [email protected]
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Abstract

We developed a new Cu–Zn wetting layer for Pb-free solders. By adding Zn to the Cu wetting layer, intermetallic growth in the Sn–Ag–Cu (SAC) solder interfaces was delayed. Cu3Sn intermetallic compounds and microvoids were not observed in the SAC/Cu–Zn interfaces after aging. The drop reliability of the SAC solder/Cu–Zn joints was excellent.

Keywords

Type
Rapid Communications
Copyright
Copyright © Materials Research Society 2009

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References

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