Dielectric trends in next-gen semiconductor packaging
Summary
Ideally, one would expect to have materials that exhibit low Dk and Df, compatible CTE with Si and Cu, high elongation value, and a moderate Young’s modulus to provide stability to the package. However, material selection entails trade-offs; for example, low Dk polymers may exhibit higher coefficients of thermal expansion (CTE), impacting device reliability and packaging architectures. However, such an approach presents challenges in establishing reliable electrical connections due to reduced bump height and surface area, necessitating precise manufacturing processes. To overcome these challenges, Cu-Cu Hybrid Bonding technology embeds metal contacts between dielectric materials and employs heat treatment for copper atom diffusion, eliminating soldering-related bridging problems and enhancing reliability in high-performance component packaging. Currently, hybrid bonding relies on inorganic dielectric materials like SiO2 or SiCN for insulation, which struggle with achieving fine-scale topography patterns and demand front-end manufacturing techniques.