Size distribution of sputtered particles from Au nanoislands due to MeV self-ion bombardment

TL;DR

This study investigates the size distribution of particles sputtered from gold nanoislands under MeV ion bombardment, revealing an inverse power-law distribution consistent with molecular dynamics simulations.

Contribution

It provides experimental data on sputtered particle size distributions from gold nanoislands under high-energy ion irradiation, aligning with theoretical models.

Findings

Sputtered particle sizes follow an inverse power-law distribution.

Average particle size and coverage were quantified.

Results agree with molecular dynamics simulations.

Abstract

Nanoisland gold films, deposited by vacuum evaporation of gold onto Si(100) substrates, were irradiated with 1.5 MeV Au$^{2+}$ ions up to a fluence of $5\times 10^{14}$ ions cm$^{-2}$ and at incidence angles up to $60^{\circ}$ with respect to the surface normal. The sputtered particles were collected on carbon coated grids (catcher grid) during ion irradiation and were analyzed with transmission electron microscopy and Rutherford backscattering spectrometry. The average sputtered particle size and the areal coverage are determined from transmission electron microscopy measurements, whereas the amount of gold on the substrate is found by Rutherford backscattering spectrometry. The size distributions of larger particles (number of atoms/particle, $n$ $\ge$ 1,000) show an inverse power-law with an exponent of $\sim$ -1 in broad agreement with a molecular dynamics simulation of ion impact on cluster targets.