Integration of a high density Ta 2O 5 MIM capacitor following 3D damascene architecture compatible with copper interconnects

Abstract

To face with the continuous integrated circuit densification, passive components size has to be reduced, particularly for RF and analog applications where lots of them are needed. A Metal–Insulator–Metal (MIM) capacitor is integrated with a high developed area architecture to increase the capacitance density and limit encumbrance. The combination of this architecture with Ta 2O 5 dielectric with a permittivity of 25 allows capacitance densities of more than 15 fF/μm 2. As metal insulator interface is critical, two stacks TiN/Ta 2O 5/TiN and TiN/Ta 2O 5/Cu are integrated among copper interconnects, evaluated and compared.