Hydrogen redistribution in thin silicon dioxide films under electron injection in high fields

Abstract

A macroscopic transport model for (i) the hydrogen redistribution in a silicon dioxide and (ii) electron-hole transport and accumulation of charge in a silicon dioxide (SiO2) layer during electrical stress are proposed in this article. The set of equations for the first model consists of two diffusion equations for the “free” atomic and molecular hydrogen and rate equations for the bound hydrogen and dangling bonds (hydrogen trap). The second model considers the kinetics of charge accumulation on the existing and new trapping centers created during electrical stress using rate equations for electrons and holes and the Poisson equation. The fitting parameters of the model have been found. Redistribution of hydrogen caused by hot-electron injection and internal photoemission for the metal-oxide-semiconductor (Al−SiO2−Si)-capacitor have been studied by a numerical simulation method. The results have been compared to experimental data.