Growth Model of Au Films on Ru(001)

TL;DR

This paper presents a simulation model for fractal growth of gold films on ruthenium, reproducing island morphology and growth kinetics, and predicting scattering intensity patterns, based on diffusion-limited aggregation and annealing effects.

Contribution

It introduces a simple DLA-based simulation model to analyze Au film growth on Ru(001), including annealing effects and growth kinetics, providing insights into fractal island formation.

Findings

Reproduces irregular fractal island morphology.

Describes growth kinetics analogous to diffusion-limited precipitate growth.

Predicts a main peak in scattering intensity due to interisland interference.

Abstract

In an attempt to find generic features on the fractal growth of Au films deposited on Ru(001), a simple simulation model based on irreversible diffusion-limited aggregation (DLA) is discussed. Highly irregular two-dimensional dentritic islands of Au particles that gradually grow on a larger host lattice of Ru particles and have fractal dimension d_{f}~ 1.70 each, are generated via a multiple had-hoc version of the DLA algorithm for single aggregates. Annealing effects on the islands morphology are reproduced assuming different sticking probabilities at nearest-neighbour lattice sites of Au films on Ru(001). Using simulation data, islands growth are described in analogy to diffusion-limited, precipitate growth with soft impingement of precipities. This leads to analyse thin film island growth kinetics in such fractal systems and to predict a main peak in scattering intensity patterns due to interisland interference. ---------------- Copies upon request to: canessae@itsictp.bitnet