Hole-mask Colloidal Lithography Research Articles

Localized Surface Plasmon Resonances in Aluminum Nanodisks

The plasmonic properties of arrays of supported Al nanodisks, fabricated by hole-mask colloidal lithography (HCL), are analyzed for the disk diameter range 61-492 nm at a constant disk height of 20 nm. Strong and well-defined (UV-vis-NIR) localized surface plasmon resonances are found and experimentally characterized with respect to spectral peak positions, peak widths, total cross sections, and radiative and nonradiative decay channels. Theoretically, the plasmon excitations are described by electrostatic spheroid theory. Very good qualitative and quantitative agreement between model and experiment is found for all these observables by assuming a nanoparticle embedded in a few nanometer thick homogeneous (native) aluminum oxide shell. Other addressed aspects are: (i) the role of the strong interband transition in Al metal, located at 1.5 eV, for the plasmonic excitations of Al nanoparticles, (ii) the role of the native oxide layer, and (iii) the possibility of using the plasmon excitation as an ultrasensitive, remote, real-time probe for studies of oxidation/corrosion kinetics in metal nanoparticle systems.

Hole–Mask Colloidal Lithography

Hole-mask colloidal lithography (HCL) represents a truly versatile and simple bottom-up nanofabrication method based on colloidal self-assembly lithographic patterning. The HCL technique provides an effective means of patterning vast surface areas with diverse functional nanoarchitectures. Examples include arrays of nanodiscs, oriented elliptical nanostructures, (binary) nanodisc pairs, nanocones on extended surfaces and nanodiscs embedded in a surrounding matrix.