Electro-migration of silver alloy wire with its application on bonding

In recent years, silver alloy wire has been widely used in semiconductor industry. In contrast to conventional gold wire, silver alloy wire has better electrical property, thermal conductivity and lower cost while tends to migrate more easily under high temperature and current density. In this paper, electro-migration (EM) of silver alloy wire after wire bonding has been studied. Under accelerated test, cracks forms not only on silver alloy wire surface but also in silver alloy wire while gold wire remain the same. Silver ion not only migrates on the wire surface also inside the wire. Temperature and current density both accelerate the EM. The conclusion could be a reference for further gold reduction of Au/Ag alloy wire in semiconductor bonding.