Numerical simulation of novel stepped hybrid bonding interface using finite element analysis

3D integration using advanced packaging and high-density chip stacking technologies has been seen as a key technological breakthrough to meet the market demand in the post-Moore era. In recent years, hybrid bonding (HB) has been regarded as a key technology for realizing high-density packaging due to its advantages such as smaller bonding space and faster electrical signal transmission. In this paper, a novel copper/polymer hybrid bonding structure is proposed, which can realize a stepped periodic bonding interface that has higher bonding strength compared with the traditional bonding interface and can effectively resist the interface failure caused by shear. The peeling stress of the bonding interface under different geometries, material parameters and process conditions is derived and compared by numerical simulation, and the risk of debonding is evaluated. It is shown that the novel structure can realize higher shear strength bonding within a wide window of process parameters.