Dissolution Behavior of Cu-0.1wt.% Fe C19210 in Molten Sn & SAC305 Solders

The dissolution behavior of trace element Fe in Cu based substrate in molten lead-free solders has been investigated. In this study, Cu-0.1wt.% Fe (C19210) dissolution was evaluated with two lead-free solders (Sn and Sn-3.0wt. %Ag-0.5wt. %Cu (SAC 305)) at temperatures 240, 270, and 300°C with reaction time of 5, 10, 20, 30, 45, 70, and 100 minutes. The results show that the two solders have similar C19210 dissolution rates at temperatures of 270 and 300°C. In addition, there was a slowdown in the formation of thin CU
3
Sn in the Sn/C19210 and SAC/C19210 reaction couple. It was found that the CU
6
Sn
5
grain size in the SAC305/C19210 couple was larger than the Sn/C19210 couple at a reaction temperature of 300°C which affected substrate consumption.