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 (Delta V(h)) component and a relatively slow and strongly T-activated interface trap (Delta V(IT)) component. The SiON process dependences are attributed to the difference in the relative contributions of Delta V(h) and Delta V(IT) to the overall degradation (Delta V(T)), as dictated by the nitrogen (N) content and thickness of the gate insulator.