RELIABILITY AND MICROSTRUCTURE OF AL-SI-V-PD ALLOY-FILMS FOR USE IN ULTRALARGE SCALE INTEGRATION

New data on a highly reliable interconnect material based on aluminum will be presented. As compared with conventional Al-Si-Cu alloy films, quaternary Al-Si-V-Pd films with only 0.1 at. % vanadium and 0.1 at. % palladium combine excellent plasma etchability with good corrosion r esistance. Electromigration tests of Al-Si-V-Pd films have shown a sur prisingly high stability at 180 degrees C. Studies of microstructural attributes show: (a) for Al-Si-V-Pd relative to Al-Si, texture is not significantly changed and average grain size is slightly increased, an d (b) the dominant factor leading to a highly stable microstructure is the combined presence of finely dispersed, small precipitates of both (Al,V) and (Al,Pd) phases.