Segregation in Pb-free Solder Joints of Surface Mount Packages Caused by Wave-soldering Process

摘要

Experiments were conducted using QFPs to study a phenomenon of ruptures due to the segregation of ingredients in QFP joints during wave-soldering of PCB with Sn-Ag-Cu-Bi solders and ways of preventing this defect were discussed. As a result, it was found that in some cases ruptures can be prevented by means of cooling the topside of PCB during wave-soldering and using Pb-free plating.