Diagnosis of Interconnect Full Open Defects in the Presence of Gate Leakage Currents

Accurate diagnosis of open defects is key to identifying process problems and achieving fast yield improvement. Current diagnosis methodologies for interconnect full open defects have demonstrated their efficiency, assuming that the defective line voltage is mainly determined by neighboring lines and downstream transistor parasitic capacitances. However, the continuous reduction of oxide thickness with every technology node increases gate leakage current significantly, even for high-k dielectrics. In this context, in nanometer CMOS technologies, the defective line cannot be assumed to be electrically isolated because of the impact of gate leakage currents, which may invalidate diagnosis results provided by present methodologies. In this paper, a new methodology is proposed to diagnose interconnect full open defects under the influence of gate leakage currents in CMOS technologies. To the authors´ knowledge, such influence has not been previously considered by any of the existing methodologies. Simulation and experimental results demonstrate the proposal efficiency.