Elimination of Cu Precipitation in Al-Cu films due to the Effect of Thermal Cycles

This paper explains how copper precipitation can be eliminated for metal-insulator-metal (MIM) dielectric capacitor processes for technology nodes larger than 0.13um with annealing at the 350-410°C range. This is shown as an effective method to eliminate aluminum blocked etch on the bottom plate of the MIM capacitor. This is essential to prevent shorting between the dense metal lines of the bottom plate and to prevent yield loss with no impact on the final electrical test or the electromigration performance.