About this Abstract |
Meeting |
2020 TMS Annual Meeting & Exhibition
|
Symposium
|
2020 Technical Division Student Poster Contest
|
Presentation Title |
SPG-22: Microstructural Evolution of High (111)-oriented Nanotwinned Copper during Direct Bonding Process |
Author(s) |
Jen-Hsuan Tsai, Yung-Ting Tai, Fan-Yi Ouyang |
On-Site Speaker (Planned) |
Jen-Hsuan Tsai |
Abstract Scope |
Cu-Cu direct bonding has become a promising method to apply to the 3D IC package. This study aimed to investigate the microstructure evolution of Cu thin films during annealing and bonding processes. Almost 100% (111) orientation nanotwinned Cu thin films prepared by the sputtering system presents high thermal stability. Furthermore, the bonding interfaces of Cu-Cu direct bonding had superior quality and the bonding ratio could achieve 80% at 250℃ without any CMP process. The phenomenon of stress-induced abnormal grain growth was observed in bonding samples and the mechanism of bonding was triggered by Nabarro-Herring Creep. Growth of tiny grains near the substrate and lateral growth further eliminate the voids and enhance the bonding quality. Finally, to simulate the 3D IC package, micro bumps were fabricated by lithography. The bonding processes of bump-film and bump-bump were achieved and the reliability test including Shear test and TCT test had excellent results. |
Proceedings Inclusion? |
Undecided |