Scan Chain Bridge Defect on a 28 nm Technology Node Circuit, Localization Using Dynamic Power Supplies

The bridge defect is one of the most difficult defects to locate. When classical static and dynamic optical techniques reach their limits, applying a dynamic signal on the power supplies for stimulating the defect allows obtaining useful additional information helping the localization. In this paper, we explore these techniques on a real case analysis of bridge defect in a scan chain on a 28nm technology node circuit. We will show that OBIRCH, LVI, static & dynamic EMMI do not give significant signatures for the defect localization. Finally we show that EMMI and LVI signatures applying a clock on the power supply bring relevant information to locate efficiently the defect.