About this Abstract |
| Meeting |
2027 TMS Annual Meeting & Exhibition
|
| Symposium
|
Electronic Packaging and Interconnection Materials IV
|
| Presentation Title |
Microstructure-Controlled Bonding and Thermal Stability in Planarized Ag–Cu Direct Bonding |
| Author(s) |
Fang-Ju Hsu, Chun-Chieh Huang, Fan-Yi Ouyang |
| On-Site Speaker (Planned) |
Fang-Ju Hsu |
| Abstract Scope |
Low-temperature direct bonding is a promising approach for heterogeneous integration but requires high interfacial integrity and thermal stability. This study investigates the bonding behavior of magnetron-sputtered Ag and Cu thin films with nanotwinned (NT) and nanocrystalline (NC) microstructures. The film surfaces were planarized by chemical mechanical polishing prior to thermal compression bonding at 250 °C under 20 MPa for 1 h. Owing to the strong (111) texture enhancing surface diffusion, NT joints exhibited a 99% bonding ratio and 44.5 MPa shear strength, significantly outperforming NC counterparts. Following post-annealing at 300 °C for 2 h, the bonding ratio of NC joints decreased to 83.1% because of grain growth and void coarsening. In contrast, NT joints maintained a 95.2% bonding ratio, as twin boundaries effectively suppressed grain boundary migration and stabilized the bonded interface. These results demonstrate that nanotwinned microstructures significantly improve bonding quality and thermal stability of Ag–Cu direct bonding. |
| Proceedings Inclusion? |
Planned: TMS Journal: Journal of Electronic Materials |
| Keywords |
Electronic Materials, Joining, Thin Films and Interfaces |