Evaporation and Step Edge Diffusion in MBE

TL;DR

This paper uses kinetic Monte-Carlo simulations to study how step edge diffusion and evaporation affect molecular beam epitaxy, proposing strategies to optimize growth in different regimes.

Contribution

It introduces two novel strategies to optimize MBE growth by controlling evaporation and step edge diffusion effects based on growth regime.

Findings

Pulsed flux reduces desorption during layer-by-layer growth.

Reducing flux with a power law promotes large, smooth 3D structures.

Strategies are applicable in different growth regimes.

Abstract

Using kinetic Monte-Carlo simulations of a Solid-on-Solid model we investigate the influence of step edge diffusion (SED) and evaporation on Molecular Beam Epitaxy (MBE). Based on these investigations we propose two strategies to optimize MBE-growth. The strategies are applicable in different growth regimes: during layer-by-layer growth one can reduce the desorption rate using a pulsed flux. In three-dimensional (3D) growth the SED can help to grow large, smooth structures. For this purpose the flux has to be reduced with time according to a power law.