Wafer-Level Mapping of Plasma-Induced Charging Effect by On-Chip In Situ Recorders in FinFET Technologies

We propose a novel approach for monitoring the wafer-level plasma-induced charging effect in advanced CMOS fin-shaped field effect transistor (FinFET) processes, and successfully demonstrate that ON-chip charge collectors, consisting of antenna-coupled floating gates (FGs), can record the plasma charging levels during back-end-of-the-line processes. The charge stored on these in situ recorders helps to project the actual potential on the transistor gates during plasma-charging stress. Wafer maps containing the potential distribution, as estimated by the level of positive and negative charging effects on the FGs, provide a powerful tool for future FinFET process optimization and yield additional insights for device reliability analysis.