• Proceedings of the KWS Conference
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• 2002.10a
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• pp.481-486
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• 2002

We have investigated the effects of plating materials for Cu lead (Sn-lOPb, AwPdJNi, Sn-3.5Ag, Sn-3Bi and Sn-0.7Cu) on properties of QFP joints using a Sn-8Zn-3Bi solder. The results were compared with the joints using Sn-3. 5Ag-0. 7Cu and Sn-37Pb solders. As a result, the joints with the Sn-3.5Ag, Sn-3Bi and Sn-0.7Cu plated Cu lead had the reliability comparable to those of the Sn-3.5Ag-0.7Cu and Sn-37Pb soldered joints with respect to the joint strength after the high temperature holding tests at 348K to 423k. In particular, the joint with the Sn-3.5Ag plated Cu lead had the best reliability. This is caused by the low growth rate of a Cu-Sn interfacial reaction layer that degrades the joint strength of the soldered joints. Consequently, the Sn-3.5Ag plating was found to be most feasible plating for the Sn-8Zn-3Bi soldered joint.