The effects of duty cycle and voltage swing of gate pulse on the AC-stress-induced degradation of nMOSFETs with N2O gate oxides
Abstract AC-stress-induced degradation in metal-oxide--semiconductor field-effect transistor (MOSFET) with N 2 O-grown and N 2 O-nitrided gate oxides was investigated, with emphasis on the duty cycle and voltage swing of the gate pulse. It is demonstrated that N 2 O-oxide devices show a weaker duty-cycle dependence than thermal-oxide devices, with N 2 O-nitrided oxide superior to N 2 O-grown oxide. More significantly, opposite frequency dependence of the V T shift is found between gate-pulse swings of 0–l/2  V D and 0– V D . The reasons are likely due to charge trapping and neutral-trap creation in the gate oxide.