Effects of Geometry and Surface Flatness on Direct Wafer Bonding by Multiphysics Modeling

This study investigates the influence of wafer geometry, surface patterning and flatness deviations on bonding performance through finite element simulations using COMSOL Multiphysics. Key findings reveal that wafer geometry and waviness delay bonding wave propagation, while etched cavity enhance bonding speed. These results highlight the critical role of wafer geometry and surface morphology in determining bonding efficiency and provide valuable insight into optimizing wafer bonding processes in 3D IC manufacturing.