Optimal conditions for boolean and current detection of floating gate faults

摘要

This paper studies the Boolean (Static Voltage) and the I{sub}(ddq) (Static Current) detection of Floating Gate faults due to large opens on transistor gate connections. We show that existing electrical models describing the behavior of FGT faults fail to allow the prediction of the floating gate potential due to the unpredictable parameters such as the initial charges and the polysilicon-to-bulk capacitance. We propose the twin-transistor structure as a basis for a general analysis of the Booleanand I{sub}(ddq) detection of FGT faults. Using this analysis, optimal conditions for detection are defined for Boolean as well as I{sub}(ddq) tests.