AC hot-carrier-induced degradation in NMOSFETs with N/sub 2/O-based gate dielectrics

Frequency-dependent ac-stress-induced degradation in MMOSFETs with N/sub 2/O-grown and N/sub 2/O-nitrided gate oxides was investigated. Suppressed device degradation is observed in both N/sub 2/O-based devices as compared to SiO/sub 2/ device for frequency up to 100 kHz, which is attributed to nitrogen incorporation in the gate oxides, Moreover, when comparing the two N/sub 2/O-based oxides, N/sub 2/O-grown oxide device exhibits enhanced degradation than N/sub 2/O-nitrided oxide device. Charge pumping measurements reveal that N/sub 2/O-nitrided oxide has better immunity to interface-state and neutral-electron-trap generation under dynamic stress.