Abstract
In this paper, FEM analysises of microelectronics solder joints subjected to cyclic thermal deformation were conducted. Pb free solder alloys (Sn-3.5Ag-0.75Cu) were chosen for the analysis, because of the regulation of using Pb/Sn solder alloys in near future. Results of Pb free solder alloys were compared with that of Pb/Sn solder alloys. Elasto-plastic, elasto-creep, and elasto-plastic-creep analysis were employed in this paper. As a result, it was found that the equivalent stress of Sn-3.5Ag-0.75Cu is much larger than that of Pb/Sn solder alloys, and that the elasto-plastic-creep analysis takes advantage of the simulation both of Pb free and Pb/Sn solder alloys.
