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A new solder wetting layer for Pb-free solders

  • Chang Yul Oh, Hee-Ra Roh, Young Min Kim, Jin Soo Lee, Hae Young Cho and Young-Ho Kim (a1)...


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.


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