Electrical and Reliability Characteristics of Self-Forming Barrier for CuNd/SiOCH Films in Cu Interconnects

In this study, Cu-2.2 at. % Nd alloy films using a co-sputtering deposition method were directly deposited onto porous low-dielectric-constant (low-k) films (SiOCH). The effects of CuNd alloy film on the electrical properties and reliability of porous low-k dielectric films were studied. The electrical characteristics and reliability of the porous low-k dielectric film with CuNd alloy film were enhanced by annealing at 425 °C. The formation of self-forming barrier at the CuNd/SiOCH interface was responsible for this improvement. Therefore, integration with CuNd and porous low-k dielectric is a promising process for advanced Cu interconnects.