Proceedings Article | 10 September 2007
Proc. SPIE. 6648, Instrumentation, Metrology, and Standards for Nanomanufacturing
KEYWORDS: Thin films, Iron, Nanoparticles, Metals, Copper, Silver, Platinum, Laser irradiation, Manganese, Nanowires
Robust nanomanufacturing methodologies are crucial towards realizing simple and cost-effective products. Here we
discuss nanofabrication of ordered metal nanoparticles through pulsed-laser-induced self-organization. When ultrathin
metal films are exposed to short laser pulses, spontaneous pattern formation results under appropriate conditions. Under
uniform laser irradiation two competing modes of self-organization are observed. One, a thin film hydrodynamic dewetting
instability due to the competition between surface tension and attractive van derWaals interactions, results in nanoparticles
with well-defined and predictable interparticle spacings and sizes with short range spatial order. The second, thermocapillary
flow due to interference between the incident beam and a scattered surface wave, results in laser induced periodic surface
structures. Non-uniform laser irradiation, such as by 2-beam laser interference irradiation, initiates a tunable thermocapillary
effect in the film giving rise to nanowires, and continued laser irradiation leads to a Rayleigh-like breakup of the nanowires
producing nanoparticles with spatial long-range and short-range order. These self-organizing approaches appear to be
applicable to a variety of metal films, including Co, Cu, Ag, Fe, Ni, Pt, Zn, Ti, V and Mn. These results suggest that
laser-induced self-organization in thin films could be an attractive route to nanomanufacture well-defined nanoparticle
arrangements for applications in optical information processing, sensing and solar energy harvesting.
