Growth rate of IMC in the binary sytems of Co/Sn and Cu/Sn

In this study we discuss superiority of Cobalt for using in 3D interconnection as alternative metal to Cu. Specimens composed of pure Sn and Co or Cu is aged under same aging condition varied time and temperature below melting point of Sn. Thickness of IMC (intermetallic compound) formed at the interface is then calculated for extraction of growth rate and kinetics like activation energy and power factor. Compared with each factors extracted from calculation, IMC formation and growth of Co/Sn has stronger time and temperature dependence than IMC of Cu/Sn. Furthermore, no voids was observed at any interface in Co/Sn bonding.