Relationship between interfacial nitrogen concentration and activation energies of fixed-charge trapping and interface state generation under bias-temperature stress condition

Abstract

The influence of nitrogen concentration at a nitrided oxide/silicon interface on the activation energies of both near-interface fixed-charge trapping and interface state generation caused by negative bias temperature instability stress has been studied quantitatively. It is observed that the charge trapping and the interface state generation have about the same activation energy for a given interfacial nitrogen concentration. In addition, their activation energies are found to follow the same dependence on the nitrogen concentration. The results suggest that the charge trapping and the interface state generation have the same origin. A discussion on the mechanism of the nitrogen effect on the charge trapping and interface state generation is presented.