Formation and stability of self-assembled coherent islands in highly mismatched heteroepitaxy

TL;DR

This paper investigates the energetics and stability of self-assembled coherent islands in highly mismatched heteroepitaxy, revealing an optimal island size and explaining the narrow size distribution through a parameter-free approach.

Contribution

It introduces a new parameter-free method to analyze island formation, accounting for wetting layer morphology and growth conditions, advancing understanding of island size control.

Findings

Optimal island size depends on coverage and density.

Critical layer thickness varies with growth conditions.

The narrow size distribution results from energetic considerations.

Abstract

We study the energetics of island formation in Stranski-Krastanow growth within a parameter-free approach. It is shown that an optimum island size exists for a given coverage and island density if changes in the wetting layer morphology after the 3D transition are properly taken into account. Our approach reproduces well the experimental island size dependence on coverage, and indicates that the critical layer thickness depends on growth conditions. The present study provides a new explanation for the (frequently found) rather narrow size distribution of self-assembled coherent islands.