| About this Abstract |
| Meeting |
2020 TMS Annual Meeting & Exhibition
|
| Symposium
|
Advanced Microelectronic Packaging, Emerging Interconnection Technology and Pb-free Solder
|
| Presentation Title |
Mechanical Reliability of Cu-filled Through Si via under Annealing and Thermal Cyclic Loading Conditions |
| Author(s) |
Dipali Shivaji Sonawane, Praveen Kumar |
| On-Site Speaker (Planned) |
Dipali Shivaji Sonawane |
| Abstract Scope |
Cu-filled-TSV is subjected to thermal expansion mismatch induced stresses during fabrication and service that can compromise structural integrity of microelectronic packages. Here, we comprehensively report effects of thermal stresses under annealing and myriad of thermal cycling conditions. Extrusion of Cu relative to Si, grain-boundary sliding, and failure of TaN barrier-layer leading to Cu-Si reaction were observed during thermal cycling between -50 and 150 oC, whereas such effects were observed only at significantly higher temperatures (250-650 °C) during static annealing. Cu-Si reaction led to nucleation of micro-cracks in Si that propagated during subsequent room temperature storage, suggesting slow crack growth in Si. Post-annealing microstructural analysis, including elemental mapping, and stress measurement using Raman spectroscopy suggest that oxidation of Si at the crack-tip and residual thermal stresses can be driving force for the slow fracture of Si. Insights gained into mechanics of the observations using finite element analysis will be discussed. |
| Proceedings Inclusion? |
Planned: Supplemental Proceedings volume |