A k-space transport analysis of the BEEM spectroscopy of Au/Si Schottky barriers

TL;DR

This paper introduces a combined Green-function and k-space Monte Carlo approach to analyze how electron transport and band structure influence the spatial resolution in BEEM measurements of Au/Si Schottky barriers.

Contribution

It presents a novel methodological combination to better understand electron dynamics and reinterpret experimental BEEM data considering band-structure effects.

Findings

Band-structure-induced directional focusing affects electron trajectories.

New insights into spatial and energetic evolution of electrons in BEEM.

Reinterpretation of existing experimental data based on band effects.

Abstract

We address the question of the spatial resolution of ballistic electron emission microscopy (BEEM) of Shottky barriers in Au(111)/Si(100) and Au(111)/Si(111) interfaces. A novel combination of Green-function and k-space Ensemble-Monte-Carlo techniques is used to obtain new insights into the spatial and energetic evolution of the STM-tip-induced electrons during their passage through the metallic layer before reaching the metal-semiconductor interface. In particular, it is shown how the effect of band-structure-induced directional focusing of the electrons enforces a reinterpretation of existing experimental data.