MICROSTRUCTURE MODULATION FOR METAL WAFER-WAFER BONDING

摘要

A three-dimensional (3D) bonded semiconductor structure is provided in which a first bonding oxide layer of a first semiconductor structure is bonded to a second bonding oxide layer of a second semiconductor structure. Each of the first and second bonding oxide layers has a metallic bonding structure embedded therein, wherein each metallic bonding structure contains a columnar grain microstructure. Furthermore, at least one columnar grain extends across a bonding interface that is present between the metallic bonding structures. The presence of the columnar grain microstructure in the metallic bonding structures, together with at least one columnar grain microstructure extending across the bonding interface between the two bonded metallic bonding structures, can provide a 3D bonded structure having mechanical bonding strength and electrical performance enhancements.