Solid-state bonding using metallic cone layer for interconnection

This paper describes the feasibility of using metallic cone layer in solid-state bonding with Sn-based solder. At temperature below the melting point of Sn, both Ni cones and Cu cones were found successful in forming robust joints with good bonding strength and compact interfaces. This method is also compatible with high-density micro bump interconnecting. Studies have also been carried out in combination with surface activation bonding. Mechanical insertion and controllable interfacial reactions functioning as key factors for realization of the bonding method were emphasized through theoretical study. This bonding method is expected to be potential for the applications in 3D integration.