Impact of Redundancy and Line Extension on Short-Length Effect in Electromigration Reliability

• Published in: Proceedings of the IEEE International Interconnect Technology Conference pp. 1 - 3
• Main Authors: Esposto, Simone, Ciofi, Ivan, Sisto, Giuliano, Croes, Kristof, Milojevic, Dragomir, Zahedmanesh, Houman
• Format: Conference Proceeding
• Language: English
• Published: IEEE 02.06.2025
• Subjects: Electromigration; parallel system; PDN redundancy; power delivery network; short-length effect
• ISSN: 2380-6338
• DOI: 10.1109/IITC66087.2025.11075449

This study investigates electromigration in a double-redundancy interconnect configuration, commonly found at standard-cell level in the power delivery networks, under downstream electron flow conditions, using both experiments and physics-based simulations. This work sheds light on the critical jL product, (jL) c , in presence of a parallel path. Due to double redundancy, for our samples coming from a 28nm commercial technology node, the critical current density j c was found to increase by 1.15-fold and 1.1-fold, for 5% and 20% R-shift failure criteria, respectively. The impact of line extension on (jL) c was also investigated. A 37% decrease in (jL) c was observed for a single line with a passive line extension acting as a sink, undermining the short-length effect, regardless of the failure criterion. For the same target lifetime, a 1.2-fold increase in maximum allowable current density, based on a 50% target failure percentile and 10 years lifetime criterion, was obtained when comparing the single and double redundancy configurations for 5% R-shift.