Failure analysis of 200 nm-thick gold interconnects induced by alternating current

A testing system for evaluation of failure behavior of gold interconnects subjected to alternating current was established. Thermal fatigue in gold lines has been investigated by using alternating currents to generate cyclic temperatures and thermal strains. It is found that the lifetime versus thermal cyclic strain range (Δε) for the 2 µm-wide Au interconnect follows the conventional Coffin-Manson relationship when Δε ≤ 0.47%, while when Δε ≫ 0.47%, the damage behavior of the Au lines is dominated by excessive Joule heating