Finite Element Analysis of the Effect of Structural Parameters and Misalignment on Bonding Strength in Fine-Pitch Hybrid Bonding

Hybrid bonding typically achieves pre-bonding of SiO<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> at room temperature, followed by thermal annealing to expand the bonding pads and establish contact, thus forming an electrical connection. However, internal stress induced by varying coefficients of thermal expansion (CTE) can impact bonding strength and stability, potentially leading to reliability issues. In this study, we analyze the effects of pad diameter and recess depth on the full pad contact temperature and internal stress for both circular and square pads using the Finite Element Analysis (FEA) method, as well as the effect of misalignment on internal stress and bonding strength. The simulation results provide valuable guidance for the design of hybrid bonding structures and control of process parameters.