| About this Abstract |
| Meeting |
2025 TMS Annual Meeting & Exhibition
|
| Symposium
|
Electronic Packaging and Interconnection Materials II
|
| Presentation Title |
Inspection, Estimation, and Design of Hybrid Bonding Processes Using In-Situ Heating Atomic Force Microscopy |
| Author(s) |
Huai En Lin, Pin Lin Chen, Chih Chen, Wei Lan Chiu, Hsiang Hung Chang |
| On-Site Speaker (Planned) |
Huai En Lin |
| Abstract Scope |
Cu/SiO2 hybrid bonding is an important process in 3D-IC fabrication. However, its unique bonding mechanism poses manufacturing challenges. In hybrid bonding, dielectric-to-dielectric bonding is first conducted at room temperature. Subsequently, chips are annealed for Cu-to-Cu bonding through Cu expansion. Since Cu expansion is only a few nanometers, Cu recess control by chemical-mechanical-polishing (CMP) becomes extremely rigorous. Estimating Cu expansion is critical for designing relevant processes of hybrid bonding.
In this study, we demonstrated the capability of in-situ heating atomic force microscopy for measuring actual Cu expansion at elevated temperatures. The dimensional effect on Cu expansion of various sizes was also examined. Results showed that Cu expansion reduced with decreasing Cu volume, suggesting more stringent requirements in fine-pitch hybrid bonding. Lastly, we provided a potential solution for fine-pitch hybrid bonding through grain-boundary engineering. By reducing grain size to the nanometer scale, Cu pad expansion increased by ~130% compared to regular Cu. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Characterization, Electronic Materials, Copper / Nickel / Cobalt |