Interface mechanics of heterogenous integration and its applications

As the semiconductor industry approaches the limits of traditional scaling, heterogeneous bonding technology has become a key enabler for the ‘More Moore’ and ‘More than Moore’ strategies. This paper provides a systematic review of the interface mechanics principles of heterogeneous bonding, with a focus on thermodynamic and shell mechanics theories. The paper explores how factors such as wettability, surface roughness, and flatness affect the physical adsorption behavior of bonding interfaces, and analyzes the surface chemical conditions required for the formation of stable covalent and metallic bonds. By integrating multiple materials, heterogeneous bonding overcomes the limitations of traditional single-chip integration systems, opening up new possibilities for high-performance, multifunctional semiconductor devices. This technology has significant applications in areas such as 3D integration, power electronics, photonics, and AI chip development. The paper also reviews the specific applications of metallic bonding, covalent bonding, and van der Waals bonding in heterogeneous integration. Ultimately, heterogeneous bonding is expected to drive the next wave of innovation in semiconductor technology, laying the foundation for more integrated and energy-efficient solutions for complex electronic systems.