Nanostructuring of thin silver films by Ar cluster ions

Abstract

In this work, we studied the formation of silver nanoparticles on silicon substrates by irradiating thin silver films with Ar⁺₁₀₀₀ cluster ions with an energy of 10 keV. The topography of the film surface was studied using scanning electron microscopy. The dependence of the particle size and their surface density on the ion fluence was described, which opens a way for controlling the geometric parameters of the particles. Particle formation was considered as a result of two competing processes: sputtering and surface migration of the film atoms. Irradiation with cluster ions at oblique incidence leaded to formation of the particles of elongated shape, with the particle height being comparable to the initial film thickness. Applicability of the particles to surface enhanced Raman spectroscopy was characterized using the dye rhodamine 6 G.