Abstract
We improved mechanical reliability of titanium-silicide interconnections for deep-submicron semiconductor devices by minimizing silicidation-induced stress. Mechanical stress develops in interconnection structures due to the shrinkage of newly grown silicide film during silicidation. Silicidation-induced stress was measured by inducing the reaction between a silicon wafer and a titanium film deposited on the wafer, and it was higher than 1 GPa. The stress developed near the interface between the grown silicide film and the remaining silicon was analyzed using a finite-element method. The critical stress for delamination at the interface was determined by comparing the results of the estimated stress at the interface with the cross-sectional observation results of test samples.
