Novel room-temperature wafer-to-wafer attachment and sealing of cavities using cold metal welding

In this paper we present for the first time a wafer-to-wafer attachment and sealing method for wafer level manufacturing of micro-cavities using a room temperature bonding process. The proposed attachment and sealing method is based on plastic deformation and cold welding of overlapping metal rings to create metal-to-metal bonding and sealing. We present the results from experiments using various bonding process parameters and metal sealing ring designs and their impact on the resulting bonds. Experiments are performed to evaluate the sealing properties against liquids and vapors of the different sealing ring structures.