Controlled dewetting as fabrication and patterning strategy for metal nanostructures

Abstract

Metal thin films and metal nanostructures find a key role in the actual nanotechnology revolution. They can be engineered for nanoelectronics, plasmonics, and sensing applications. However, the crucial step toward reliable technological applications of metal‐based nanodevices is the development of simple, low cost, versatile, and high‐throughout nanofabrication methodologies. In general, top‐down nanofabrication approaches allow a minimum size of the single nanostructure higher than 10 nm, a high control on spatial regularity and size of the nanostructures, but involve high cost and long processing time. In contrast, bottom‐up approaches allow a minimum size of the single nanostructure lower than 10 nm, a low control on spatial regularity and size of the nanostructures, but involve low cost and short processing time. In this paper, the controlled dewetting process of thin metal films on surfaces is reviewed as a patterning and nanofabrication method for metal‐based nanocomposites, crossing the strenghts of both approaches.

Characteristics of Pd and Pt Nanoparticles Produced by Nanosecond Laser Irradiations of Thin Films Deposited on Topographically-Structured Transparent Conductive Oxides

“…The molten-phase dewetting process of the Pd and Pt films is observed to lead to the formation of NPs for which the mean diameter <D> and mean surface density <N> are quantified. Our results show, in particular, the effect of the FTO surface topography on the resulting NPs size through the geometry-dependent chemical potential, an effect which is absent for the dewetting phenomenon of thin metal films on flat surfaces [22][23][24][25][26][27][28][29][30][31][32]. This effect is discussed starting from previous results on metallic film dewetting occurring on intentionally patterned surfaces [33][34][35][36].…”

“…FTO is a transparent conductive oxide which use is largely diffused as coating in solar cell devices or for photoelectrochemical reactions on surface [15][16][17][18][19]. Then, nanosecond laser irradiations were carried on the metallic films surface so to exploit the potentialities of the laser-matter interaction for surface nanostructuration [20][21][22][23][24][25][26][27][28][29][30]. In particular, we processed, by the laser pulse, Pd or Pt films of various thickness d [20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37].…”

Substrate Dependence in the Formation of Au Nanoislands for Plasmonic Platform Application

“…On the other hand, in the cases of thin and ultra-thin layers, the leading process of nanostructure growths seems to be solid-state dewetting. It is widely discussed in the literature that the formation of nanostructures is based on nucleation of holes and their later growth [2,[16][17][18][19]. Nucleation can take place in two ways: as homogeneous nucleation, when holes appear as a consequence of small thermal density fluctuations.…”

Self‐Organization Based Fabrication of Bimetallic PtPd Nanoparticles on Transparent Conductive Oxide Substrates

“…In this case, characteristic length scales emerge which vary with film thickness . In particular, the NPs obtained by this process should be characterized by mean diameter < D > which can be expressed, as a function of the initial film thickness h , by a power‐law relation . However, even if the spinodal dewetting process should be the dominant nano‐structuration mechanism, in our case, it occurs for the Pt‐Pd bilayers on a structured surface (the pyramidal structured FTO surface).…”