Mechanism and Application of Negative Charging Mode of Electron Beam Inspection for PMOS Leakage Detection

In this study, we modified surface condition of tungsten chemical mechanical polish (WCMP) to resolve the mix mode issue and achieved and optimized negative mode electron beam inspection (EBI). We detected dark voltage contrast (DVC) defects on static random access memory (SRAM) array at PMOS contacts. Physical failure analysis (PFA) results confirmed prediction that they are P+/N-well junction leakages caused by nickel silicide (NiSi_x) spiking.