Interfacial reaction and elemental redistribution in Sn3.0Ag0.5Cu-xPd/immersion Au/electroless Ni solder joints after aging

► Pd doping has significant effect on the microstructural development of Sn3.0Ag0.5Cu solder. ► The growth of intermetallics reduced by adding Pd. ► Pd mainly dissolved in Cu6Sn5. ► Adding Pd into the solder improves stability of the intermetallics.