Low-Temperature Wafer Bonding Using Solid–Liquid Inter-Diffusion Mechanism

Abstract—The low temperature joining of semiconductor substrates on wafer level by solid–liquid inter-diffusion bonding using the Cu/Ga and Au/In systems is investigated regarding the bonding parameters and their influence on bond interface properties. The focus is on temperature dependence and composition of interface. In the case of Cu/Ga bonding, a phase transition from CuGa2 to Cu9Ga4 …