Interfacial Reaction of Sn-Ag-Cu Lead-Free Solder Alloy on Cu: A Review
Figure 11
Growth mechanism of Cu-Sn IMCs at various reflow times: (a) formation of scallop Cu6Sn5 at the SAC305/Cu interfacial region, (b) appearance of Cu3Sn between the Cu6Sn5/Cu interface, and (c) increase in both Cu-Sn IMCs thicknesses with increasing reflow times.