A Novel Method for the Determination of Electromigration-Induced Void Nucleation Stresses

• Published in: 2024 IEEE International Reliability Physics Symposium (IRPS) pp. 10A.4-1 - 10A.4-6
• Main Authors: Shuster-Passage, J., Razek, S. Abdel, Mattoo, M., Hauschildt, M., Choi, S., Gall, M., Kteyan, A., Choy, J.-H., Sukharev, V., Kraatz, M., Lloyd, J. R.
• Format: Conference Proceeding
• Language: English
• Published: IEEE 14.04.2024
• Subjects: Bridges; Calibration; critical stress; Cu interconnect; early failure; Electromigration; Kelvin; nucleation; Reliability; Statistical distributions; statistics; Stress; void growth; Wheatstone Bridge
• ISSN: 1938-1891
• DOI: 10.1109/IRPS48228.2024.10529368

The experimental determination of electromigration-induced critical stresses leading to void nucleation has been a complex endeavor across the past several decades. In this study, we propose a combination of single link electromigration testing, augmented by large scale statistical evaluations using Wheatstone Bridges, as well as detailed physics-based simulations to arrive at the extraction of the critical stresses which lead to void nucleation and further growth. The calibration efforts lead to well-matched values in terms of basic physical parameters such as effective diffusivity \boldsymbol{D}_{\boldsymbol{eff}} , charge number \boldsymbol{Z}^{\ast} and effective modulus \boldsymbol{B} . Furthermore, the statistical distribution of single link Kelvin structure and Wheatstone Bridge failure times is reproduced very well, ruling out an early nucleation mechanism close to the 4-sigma level. The calibration of the complex simulation model, based on a large experimental database, opens up the path to a much-improved chip-level reliability assessment process.