Synthesis of aligned nanoparticles on laser-generated templates

Abstract

A fast and simple technique that produces self-aligned gold nanoparticles on a silicon substrate, covering a large area, is described. This technique involves three consecutive steps: first, the substrate is laser-irradiated to produce a periodic nanorippled structure; second, a thin film of gold is grown using ion-beam sputter deposition; and third, a thermal treatment is conducted to produce the formation and self-alignment of nanoparticles. The nanoparticles form along strips parallel to the nanoripple lines. The strip spacing equals the nanoripple spacing and the strip width depends on the angle of deposition and the divergence of the ion beam. The nanoparticle diameter is a function of the annealing temperature and time. It was found that deposition of the film at a very shallow grazing angle (0 • ) induces, upon thermal annealing in air at 800 • C, the formation of single nanoparticle rows aligned along the ripple ridges. In order to obtain the single-particle lines, a beam collimator, aimed at reducing the angular spread of the incident ion beam, was employed during deposition.This technique is general and could be used in a large number of substrate/film combinations. Studies of other substrates would provide optimum conditions to obtain similar results, as laser-induced periodic structures are a fairly universal phenomenon.

Nanostructuring of thin Au films by means of short UV laser pulses

“…This is due to such advantages as the broad plasmon resonance in the UV−visible−near infrared region, high stability of the structures, and reliable preparation techniques [3][4][5]. The lithographic ones by means of elec− tron and ion beams, electrospraying, and direct laser 2D and 3D structuring belong to the well proven [6,7]. For sil− ver, the nanoparticle patterning by the pulsed−laser abla− tion of a silver target and deposition on a glass surface both performed in water is reported and then found to be a highly effective surface−enhanced Raman scattering sub− strate [8,9].…”

Biomimetic structures for mechanical applications by interfering laser beams: More than solely holographic gratings

“…If the system is melted periodically, dynamic processes due to surface tension and viscosity can be used to realize separation effects. Guan et al 20,21 aligned nanoparticles on surfaces by the use of interference phenomena and shows a LRO periodic structure. The nanoparticles are produced due to separations of the dynamic melting pool and show a SRO particle distribution (see Fig.…”

Phase‐Modulated Hierarchical Surface Structures by Interfering Laser Beams

“…al. [24,25] aligned nano-particles on surfaces. The alignment was achieved by the use of interference phenomena and showed a LRO, while the nano-particles were produced due to separations of the dynamic melting pool and showed a SRO on the top of the interference driven alignment (Fig.…”

“…[21,24,31] Generally, the lowest physical length limit for the spacing of the interference fringe according to Equation 2 is half of the laser wavelength. This limit can be pushed down by changing the wavelength just above the sample.…”