Stress voltage polarity dependence of JVD-Si3N4 MNSFET degradation

Abstract

In this paper, we study the stress voltage polarity-dependent reliability of n-channel metal-nitride-silicon field-effect transistors (MNSFETs) with ultrathin jet vapor deposited (JVD) silicon nitride dielectric. Under constant voltage stress, device parameters such as threshold voltage and transconductance degrade. Charge trapping due to interface and bulk traps is observed. Our study shows that the degradation is polarity dependent. MNSFETs show lower degradation under positive stress fields. We have also compared the performance of MNSFETs with conventional MOSFETs under identical stress conditions. Under positive stressing, MNSFETs clearly outperform MOSFETs, but under negative stressing, MNSFETs show more degradation.