A common framework of NBTI generation and recovery in Plasma-nitrided SiON p-MOSFETs

Abstract

Generation and recovery of degradation during and after Negative Bias Temperature Instability (NBTI) stress are studied in a wide variety of Plasma-nitrided (PN) Silicon Oxynitride (SiON) p-MOSFETs. An ultrafast on-the-fly Linear Drain Current (I_DLIN) technique, which is capable of measuring the shift in threshold voltage from very short (approximately in microseconds) to long (approximately in hours) stress/recovery time, is used. The mechanics of NBTI generation and recovery are shown to be strongly correlated and can be consistently explained using the framework of an uncorrelated sum of a fast and weakly temperature (T)-dependent trapped-hole (¿V_h) component and a relatively slow and strongly T-activated interface trap (¿V_IT) component. The SiON process dependences are attributed to the difference in the relative contributions of ¿V_h and ¿V_IT to the overall degradation (¿V_T), as dictated by the Nitrogen (N) content and thickness of the gate insulator.