Effect of the trap level of the silicon nitride layer on the retention characteristics of GAA-MONOS charge trap memories at elevated temperature

Abstract

We present an investigation for the retention characteristics of 3-Dimensional (3D) GAA MONOS cells. The phenomenon of retention charge loss at elevated temperature in 3D GAA MONOS cells has been experimented and studied by 3D TCAD simulation. Simulated retention characteristics are compared with experiment results measured GAA MONOS cells is consisted of metal gate, 4 nm tunnel oxide, 5 nm silicon nitride and 6 nm blocking oxide. Especially, we considered the trap level dependence in silicon nitride layer having Gaussian trap distribution on retention characteristics of GAA MONOS cells. Simulation results showed that shallow energy levels significantly affect the retention charge loss compared to deep energy levels in silicon nitride layer. From these results, the simulation results for the retention characteristics of GAA MONOS cells were in reasonable agreement with the experimental results.