Tailoring Plasmon Resonances in Aluminium Nanoparticle Arrays Fabricated Using Anodic Aluminium Oxide

Abstract

biomolecules that have small Raman cross sections in the visible and NIR regions. [ 2 ] However, interband transitions introduce a dissipative channel for Au and Ag plasmon resonances at wavelengths shorter than 550 and 350 nm, respectively. aluminium (Al) has recently been suggested as promising plasmonic material in the UV and DUV regions because it has negative real part of dielectric function down to a wavelength of ≈100 nm. [ 3 ] The sharpness and intensity of LSPR of small Al NPs improve with increasing energy. The excellent optical properties of Al make it an excellent material for UV nanoantennas, [ 4 ] DUV SERS, [ 2,5 ] lightemission enhancement of wide-bandgap semiconductors, [ 6 ] and improvement of light harvesting in solar cells. [ 7 ] Moreover, Al is signifi cantly cheaper than most other metals, and could potentially serve as the metal of choice for either complementary metal-oxide-semiconductor (CMOS) compatible or mass-producible plasmonic applications.Controllability of LSPR energies is highly required for plasmonic applications. For instance, DUV-SERS of adenine on Al nanostructures requires their resonance peaks close to the excitation wavelength to ensure high-electromagnetic nearfi eld enhancement. [ 2,5 ] LSP-enhanced DUV light-emission in AlGaN multiple quantum wells desires large spectral overlap between the plasmon resonance of Al NPs and the bandgap of active layer. [ 8 ] Al NPs are generally designed with the help of electron beam lithography (EBL) and focused ion beam (FIB) lithography in order to obtain well-controlled structures. [ 4 , 7b , 9 ] However, these approaches involve a slow process and are not cost effective, so that they are not practical for large area (square cm) fabrication. Although Al NPs can be fabricated by modifi ed methods of annealing thin Al fi lm, [ 10 ] such techniques often lead to signifi cant size dispersion, and it is diffi cult to tune the size and interval of particles independently. Anodic Al oxide (AAO), which is prepared by the anodic oxidation of Al in an acidic electrolyte, is one of the typical self-organized fi ne structures with a nanohole array. Using AAO as an evaporation or electrodeposition mask, ordered NP arrays can be formed. [ 11 ] This process has several advantages: each particle has almost identical size and spacing, the size and the spacing can be easily controlled by changing the geometrical structure of the AAO mask, there is no practical limitation to the size of the AAO template, so that very large panels of NPs can be made with low cost. However, to the best of our knowledge, the study

Super Absorbing Ultraviolet Metasurface

“…This dimension can be realized using low-cost and large area fabrication techniques like nanoporous anodic alumina. In a latest experimental report [21], Al nanopattern arrays were successfully fabricated with the average particle dimension of ∼55 nm, which could be optimized further to fabricate the proposed UV metasurfaces.…”

“…4(b), which should be realizable using inexpensive nanofabrication techniques (e.g. nanoporous anodic alumina lithography [21]). Finally, in terms of potential oxidation issue of Al-based structures, it has been reported that ultrathin oxide protective layers on top of Al patterns may prevent further oxidation and corrosion and result in chemically stable biosensors [33].…”

Adaptive gold/vanadium dioxide periodic arrays for infrared optical modulation

“…Au is non-miscible with vanadium, so there is no possibility of alloys. Thereby, it constitutes the ideal candidate for evaluating the QTP geometric changes as a function of temperature [41] and for the development of a vanadium based nanocomposite. Al2O3-c substrates are used due to their high chemical and thermal stability and their lack of reactivity with Au.…”

Abnormal dewetting of Ag layer on three-dimensional ITO branches to form spatial plasmonic nanoparticles for organic solar cells

“…To maximize the effects of LSPs in the active layer of OSCs, the shape of NPs are important 11 – 13 . So, various geometric structures of metal nanowires 23 , nanoclusters 24 , nanocubes 17 , 18 , 37 , and nanoprisms 43 , have been studied using nanotechnology such as electron beam lithography 46 , UV-nanoimprint lithography 47 , etched anodic aluminum oxide 48 , and so on. However, many of these methods have limitations such as high-temperature process, high cost, reproducibility, and especially, complexity of fabrication.…”