Physical modeling of program and erase speeds of metal-oxide-nitride-oxide-silicon cells with three-dimensional gate-all-around architecture

Abstract

We present an investigation of the program and erase speed characteristics of three-dimensional (3D) gate-all-around (GAA) metal-oxide-SiNx-oxide-silicon (MONOS) cells. The effect of the tunneling oxide layer thickness in 3D GAA MONOS cells has been experimentally investigated and studied by 3D technology computer-aided design (TCAD) simulation. In particular, we considered physical parameters such as trap density, capture cross section, and trap level in order to analyze the physical properties of the silicon nitride layer. Simulation results indicated that the trap density significantly affects the program efficiency compared with other physical parameters, and the trap level mainly affects the erase efficiency. From these simulation results, we confirmed from the experimental results that the modeling accuracy is about 80%. Moreover, the simulation results for the program and erase speeds of the GAA MONOS cells were in reasonable agreement with experimental results.