Determination of Cu-line EM Lifetime Criteria Using Physically Based TCAD simulations

Abstract

A physically based simulation methodology provides fast and practical EM lifetime prediction. We identified an “EM-aware” region to define the length dependence of Cu-lines under high current stress. For eventual calibration of 2× nm node Cu-lines, we analyzed the sensitivity trends of vacancy and void profiles as well as the mass transport mechanisms using a 3D TCAD tool. This includes electron flow dependency to explain line and via depletion effects for void formations under various EM stress conditions. We report a non-linearity in the length dependence on the EM failure jL product at ~9000 A/cm and a slight temperature dependence on the Blech Threshold (jL)c at ~2000 A/cm extracted at 300°C in the EM aware region.