TCAD simulation for capture / emission of carriers by traps in SiN: trap-assisted tunneling model extended for capture of carriers injected via Fowler-Nordheim tunneling

Abstract

Abstract We propose the novel trap-assisted tunneling (TAT) model that incorporates the ability to calculate dissipation of the kinetic energy of carriers propagating in the conduction or valence band. The proposed model allows us to evaluate capture efficiency (or the capture cross section) of carriers injected into the SiN charge trap layer via Fowler-Nordheim tunneling. By applying our TAT model to large planar Metal-Oxide-Nitride-Oxide-Semiconductor (MONOS) capacitors, experimental data showing that electron capture efficiency depends on the tunnel oxide thickness are physically interpreted. Furthermore, 3-dimensional technology computer-aided design (TCAD) simulation using SiN trap parameters roughly extracted from planar MONOS data shows that the calculated incremental step pulse programming characteristics of the charge trap memory (CTM) prototype device are comparable with measured data. We have found that additional time to calculate SiN trap charges is less than only 5 % of all remaining calculation time.