Atomistic Modeling Of Nanoscale Ferroelectric Capacitors Using a Density Functional Theory And Non-Equilibrium Green’s-Function Method

Abstract

We propose a first-principles atomistic method based on density functional theory and the non-equilibrium Green’s-function method to investigate the electronic and structural response of metal-insulator-metal capacitors under applied bias voltages. We validate our method by showing its usefulness in two paradigmatic cases where including finite-bias structural relaxation effects is critical to describe the device behavior: formation of dielectric dead layers in a paraelectric SRO|STO|SRO capacitor due to an applied bias voltage, and the switching behavior of a ferroelectric SRO|BTO|SRO capacitor due to an external electric field.