Hybrid bonding enables the commercialization of ultra‐fine pitch high‐density 3D packages. Cu/SiO2 hybrid bonding is the standard packing interface recently introduced in the industry. Here, the Cu/polymer hybrid bonding interface beyond Cu/SiO2 is proposed in order to have high compatibility for additional processes in the future. Ideally, polymers can provide excellent bonding strength and low permittivity, enabling high‐speed signal transmission with high reliability. To realize it, optimum polymer and additives selection and polymer bonding processing development are needed to get the desired packaging interface. Therefore, detailed materials and processing challenges are discussed to realize the successful Cu/polymer hybrid bonding. Then, the authors’ preliminary results are suggested to supplement the feasibility of the emerging bonding technology.

Cu interconnects suffer from increased resistance and poor reliability at a sub-10 nm width. Ru and Mo have been highlighted recently as the next interconnection material candidate due to their various advantages over Cu; they have lower resistance than Cu at sub-10 nm, do not diffuse into SiO2, and are etchable. Here, we evaluated the electromigration (EM) reliability of Ru and Mo to confirm their feasibility for the next-generation interconnection. The activation energy for EM failure is calculated by measuring the mean time to failure (MTTF) of film and wire structures while factoring in temperature increases with thermal coefficient of resistance (TCR) measurements. In addition, we investigate the EM properties in terms of resistivity-increasing parameters that originate from geometry and additional fabrication processes. Furthermore, we evaluate the EM performance in terms of electrochemical potential. Our findings confirm the feasibility of Ru as a promising candidate for next-generation interconnection applications, providing enhanced reliability compared to conventional Cu interconnects.

Recently, Cast-In-Steel Shell(CISS) pile has been used as the foundation of bridges and a pier is directly connected to the pile. In this case, plastic hinge is generally formed at the connection between the pile and pier. To increase the flexural capacity of such structure, a proper improvement method is necessary for the connection. In this study, a steel tube has been used to enhance flexural capacity of the connection and the effect by the such method was evaluated through a series of 3-dimensional finite element method analysis and experimental studies. From the analysis and test results, it can be found that the flexure capacity is considerably increased by applying the steel tube at the connection.