Abstract: 

The authors modified the charge decay model of silicon-oxide-nitride-oxide-silicon-type memory at the temperatures above 150°C⁠. The modified model includes the effect of the internal electric field induced by the charges trapped in silicon nitride layer. The authors extracted the trap density distributions in energy level of the Si-rich silicon nitride using the model and compared them with those of stoichiometric silicon nitride. It has been revealed that the Si-rich silicon nitride has larger trap density in shallow energy level than the stoichiometric silicon nitride and this relation is reversed as the energy level goes deeper.