Cu-Sn Transient Liquid Phase Wafer Bonding: Process Parameters Influence on Bonded Interface Quality

Abstract

Cu-Sn Transient Liquid Phase (TLP) wafer-level bonding is an interesting solution for wafer-to-wafer stacking technologies, due to its compatibility with 3D interconnections as well as vacuum sealing applications. The work presented here is analysing typical Cu-Sn TLP wafer bonding issues as occurrence of voids, bonded wafers pair bow and incomplete layer transformation with respect to process parameters as maximum bonding temperature, bonding time and contact (bonding) pressure.