Process loading reduction on SADP FinFET etch

In this paper, we investigated the dense-isolated loading topics in Self-Aligned-Double-Patterning (SaDP) FinFET etching process from the point of view of etching parameters. The introduction of pulsing plasma plays an important role on suppressing dense-isolated loading in both core and shallow trench isolation (STI) etch. Besides, film stack selection is also very critical for loading control. We summarized the loading control trend in both core and STI etch. Based on the experimental and theoretical learning, we successfully delivered a FinFET STI etching process for 14 nm technology node.