Enhancing EM Reliability and Lifetime Modeling: A Multi-Link Structure Approach.

With the increasing demands of lower RC and higher interconnect density in scaling technology, an accurate electromigration (EM) reliability modeling without sacrificing lifetime performance becomes crucial. In this work, an efficient multi-link EM pattern was proposed to have a better understanding of fabrication defects and low-percentile EM reliability modeling in the dual-damascene process. Without collecting over thousand samples, the proposed multi-link EM patterns successfully validated lognormal based 3-parameter (t50, σ and X0) at <1% lifetime extrapolation based on weakest link statistics. The improved lifetime and higher current density, achieved through an efficient stress sampling plan to meet EM reliability specifications, highlights the significance of an accurate low-percentile EM reliability model with a multi-link structure to enable transistor scaling in back-end-of-line (BEOL) process innovations.