Interfacial engineering of nitrogen-doped silicon carbide for reliable hybrid bonding in advanced semiconductor integration

Abstract

Hybrid bonding is emerging as a key enabler for ultrahigh-density three-dimensional semiconductor integration driven by high-performance computing (HPC) and artificial intelligence (AI) applications. By enabling direct metal–metal and dielectric–dielectric bonding to achieve coplanar electrical and mechanical interconnections, it provides a viable pathway beyond the limits of conventional transistor scaling. Achieving high bonding quality critically depends on precise control of dielectric interfaces, where specific surface and subsurface chemical reactions govern bond formation. Nitrogen-doped silicon carbide (SiCN) has recently attracted significant attention as an alternative to conventional SiO₂ dielectric due to its tunable chemical configurations, strong resistance to Cu diffusion, and reduced interfacial void formation. Recent advances have clarified how the interfacial structure of SiCN influences interfacial water consumption, gap closure, and the formation of robust chemical bonds during bonding, establishing a mechanistic link between material chemistry and bonding performance. This review systematically examines the latest developments in SiCN interfacial engineering, including film fabrication, bonding mechanisms, and structure–property relationships that govern bonding performance. It also highlights outstanding challenges and emerging opportunities, including low-temperature deposition techniques, activation mechanism investigations, analysis of interfacial water consumption dynamics, co-optimization of SiCN and Cu bonding processes, management of interfacial thermal resistance and stress, and AI-accelerated materials discovery, offering a forward-looking perspective on future research directions in this advancing field.