Interface reaction between SnAgCu/SnAgCuCe solders and Cu substrate subjected to thermal cycling and isothermal aging

► Interface reaction mechanism, experienced thermal cycling and isothermal aging, was carried out. ► The growth kinetics which forming intermetallic compounds in both systems were also investigated under different aging conditions. ► We found that the morphology of IMCs formed both at the solder/Cu interfaces was gradually changed from scallop-like to planar-like. ► We found that rare earth Ce can refine the microstructures, decrease the thickness of the intermetallic compound layer.