Variability study of MP18 semi-damascene interconnects with fully self-aligned vias

Abstract

In this work, process modeling was coupled with actual Si data to perform process optimization and control of an 18nm metal pitch (MP18) semi-damascene flow with fully self-aligned vias (FSAV). We explored the impact of process variations and patterning sensitivities on line and via resistances as well as on line capacitance variability. We also benchmarked capacitance variability using partial-airgap and gap fill options. From this study, we have identified significant process parameters and corresponding process windows that need to be controlled to ensure successful manufacturability of the MP18 semi-damascene flow.