Abstract
In this study, 5 [mil] aluminum wire bonds are subjected to elevated ambient temperatures, current densities, and mechanical stresses using a novel accelerated testing mechanism. Failure of a wire bond in this study was a 10 % increase in electrical resistance. Temperature coefficient of resistance experiments in this study identified the wire temperatures resulting from joule heating and thermomechanical stress evaluations were completed using ANSYS to extract relevant stresses occurring at each experimental condition. Collection of the failure data and analysis of the results indicate that mechanical stress interacts with current density and that the introduction of externally applied mechanical stress reduces the lifetime of a wire bond. Comparisons have been drawn between time to failure estimates for Black's equation for electromigration and three model forms developed from the results of this study. The comparison indicates that Black's equation is insufficient when mechanical stresses interact with current density and that mechanical stress ought to be considered in the future when completing reliability evaluations for wired interconnects in high-temperature systems.
| Original language | English |
|---|---|
| Article number | 115185 |
| Journal | Microelectronics Reliability |
| Volume | 149 |
| DOIs | |
| State | Published - Oct 2023 |
| Externally published | Yes |
Funding
The authors would like to thank the Korea Electrotechnology Research Institute, the center for Power Optimization of Electro-Thermal Systems, the National Science Foundation (Grant No.: 2014-00555-04), the Defense Established Program to Stimulate Competitive Research, and the Office of Naval Research (Contract No.: FA9550-21-1-0205; Approved paper DCN#: 543-347-23) for funding and guidance to make this study possible. The authors would also like to the University of Arkansas College of Engineering and Mechanical Engineering department as well as the High Density Electronics Center for access to facilities, equipment, and resources needed for the creation of this study. Any opinions, findings, and conclusions or recommendations expressed in this content are those of the author(s) and do not necessarily reflect the views of the Korea Electrotechnology Research Institute, National Science Foundation, or the Office of Naval Research. The authors would like to thank the Korea Electrotechnology Research Institute , the center for Power Optimization of Electro-Thermal Systems, the National Science Foundation (Grant No.: 2014-00555-04 ), the Defense Established Program to Stimulate Competitive Research, and the Office of Naval Research (Contract No.: FA9550-21-1-0205 ; Approved paper DCN#: 543-347-23) for funding and guidance to make this study possible. The authors would also like to the University of Arkansas College of Engineering and Mechanical Engineering department as well as the High Density Electronics Center for access to facilities, equipment, and resources needed for the creation of this study. Any opinions, findings, and conclusions or recommendations expressed in this content are those of the author(s) and do not necessarily reflect the views of the Korea Electrotechnology Research Institute, National Science Foundation, or the Office of Naval Research.
Keywords
- Accelerated testing
- Al wire bonds
- Electromigration
- Interacting failure mechanisms
- Power electronics
- Thermomechanical stress