Atomistic Simulation of Defect Processes Involved in the Reaction-Diffusion-Drift Model of NBTI

Density functional theory (DFT) simulations are used to model hole trapping reactions at hydrogencontaining defects in the bulk of amorphous $\mathrm{SiO}_{2}\left(\mathbf{a}-\mathrm{SiO}_{2}\right)$ in the context of the reaction diffusion drift (RDD) model of NBTI. We report hole trapping, proton dynamics, and hydrogen release mechanisms related to bulk trap generation in the presence of hot holes, involving oxygen vacancies passivated by hydrogen $\left(\mathrm{H}_{2}-\mathrm{V}_{O}\right)$ and water $\left(\mathrm{H}_{2} \mathrm{O}-\mathrm{V}_{O}\right)$. The charge transition levels (CTLs) and reaction barriers of these defect processes were calculated to predict their behavior under varying Fermi levels in metal-oxide-semiconductor field-effect transistors (MOSFETs) providing new insights into how these defects evolve during NBTI stress.