A Dual Strategy of Electroless Metal Deposition and Silylation for Targeting Low-temperature Hybrid bonding

초록

Low-temperature Cu/SiO2 hybrid bonding has emerged as a key technique for advanced semiconductor packaging. In this study, Cu/SiO2 hybrid bonding is successfully achieved by rapid processing approach that combines electroless deposition (ELD) with silylation methods. A thin noble metal layer is first deposited onto the Cu surface via ELD, and the SiO2 dielectric layer is selectively functionalized using a hydrophilic silane precursor. A pre-bonding is performed under vacuum at 120?°C, followed by annealing at 250?°C. Accordingly, Cu-to-Cu bonding with a minimal gap of ca. 10?nm is achieved at the relatively low temperature of 250?°C. These results demonstrate that the dual strategy of metal and silane-based ELD provides a viable and practical approach for low-temperature Cu/SiO2 hybrid bonding, offering promising solutions for next-generation advanced packaging processes. - 본 연구는 2025년도 산업통상자원부 및 산업기술기획평가원(KEIT) 연구비 지원에 의한 연구임(RS-2022-00156073). Keywords: Electroless deposition, Silylation, Low temperature, Cu/SiO2 hybrid bonding, Advanced packaging.