First-Principles Theory for Schottky Barrier Physics

TL;DR

This paper presents a comprehensive first-principles approach to calculating Schottky barrier properties by integrating a self-consistent solution of the Poisson equation with DFT, enabling detailed atomic-scale modeling.

Contribution

It introduces a novel method that combines Poisson equation solving with DFT to compute Schottky barriers from first principles for large atomic systems.

Findings

Successfully computes Schottky barrier heights from atomic-scale models.

Accounts for doping, band bending, and evanescent states in the barrier.

Enables simulation of barriers involving thousands of atomic layers.

Abstract

We develop a first-principles theory for Schottky barrier physics. The Poisson equation is solved completely self-consistently with the electrostatic charge density and outside the normal density functional theory (DFT) electronic structure iteration loop, allowing computation of a Schottky barrier entirely from DFT involving thousands of atomic layers in the semiconductor. The induced charge in the bulk consists of conduction and valence band charges from doping and band bending, as well as charge from the evanescent states in the gap of the semiconductor. The Schottky barrier height is determined when the induced charge density and the induced electrostatic potential reach self-consistency.