RELATION BETWEEN STRESS-INDUCED LEAKAGE CURRENT AND DIELECTRIC-BREAKDOWN IN SIN-BASED ANTIFUSES

We report on the degradation process of metal-to-metal antifuses that use thin silicon nitride him as the dielectric layer under high electr ic field stress. Stress-induced leakage current was observed in ail sa mples, and it flows through local spots. Two-level fluctuations were f ound on the leakage current well below the stress voltage, and large a nd complex fluctuations were observed near the stress voltage. The con duction mechanism of the stress-induced leakage current was the Poole- Frenkel type. It was found that the dielectric constant of the path be came large and that the breakdown and the anomalous current depended o n the barrier metal thickness. Considering these results, the stress-i nduced leakage current and the breakdown are thought to be caused by e lectromigration of electrode material to the SiN film.