About this Abstract |
| Meeting |
2026 TMS Annual Meeting & Exhibition
|
| Symposium
|
Phase Stability, Phase Transformations, and Reactive Phase Formation in Electronic Materials XXV
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| Presentation Title |
Cu Migration and Whisker Formation in Cu₃Sn Intermetallics Under High Temperature and Current Stress |
| Author(s) |
Albert T. Wu, Jui-Lin Chao, Kelvin Li, Chang-Meng Wang |
| On-Site Speaker (Planned) |
Albert T. Wu |
| Abstract Scope |
This study investigates atomic diffusion in Cu₃Sn intermetallic compounds under high temperature and high current conditions. Cu₃Sn thin films are fabricated by co-sputtering on U-groove silicon substrates and annealed for phase uniformity. To block oxygen and mimic device environments, selected samples are coated with a SiO₂ layer. Thermomigration and electromigration tests are conducted at 150, 250, and 300 °C under a current density of 1 × 10⁵ A/cm². Results identify Cu as the dominant diffusing species, leading to Cu-rich surface segregation, Sn-rich bottom regions, and degradation of crystallinity. Current stress accelerates Cu migration, induces whisker formation, and enhances phase decomposition. The SiO₂ layer retards Cu segregation and whisker growth by limiting oxygen ingress. At 300 °C, coefficient of thermal expansion mismatch causes plastic deformation, enabling Cu to penetrate the SiO₂ layer and form oxides. This work clarifies thermomigration and electromigration effects in Cu₃Sn, advancing the understanding of interconnect reliability in high-power electronics. |
| Proceedings Inclusion? |
Planned: |