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Ordered nanostructure arrays have attracted intensive attention because of their various applications. However, it is still a great challenge to achieve ordered nanostructure patterning over a large area (such as wafer-scale) by a technique that allows high throughput, large pattern area and low equipment costs. Here, through a unique design of the fabrication and transferring processes, we achieve a facile transferring of wafer-scale ultrathin alumina membranes (UTAMs) onto substrates without any twisting, folding, cracking and contamination. The most important in our method is fixing the UTAM onto the wafer-scale substrate before removing the backside Al and alumina barrier layer. It is also demonstrated that the thickness and surface smoothing of UTAMs play crucial roles in this transferring process. By using these perfectly transferred UTAMs as masks, various nanostructure patterning including nanoparticle, nanopore (nanomesh) and nanowire arrays are fabricated on wafer-scale substrates with tunable and uniform dimension. Because there are no requirements for UTAMs, substrates and materials to be deposited, the method presented here shall provide a cost-effective platform for the fabrication of ordered nanostructures on large substrates for various applications in nanotechnology.

Perfectly ordered nanoparticle arrays are fabricated on large-area substrates (cm(2)) via a cost-effective nonlithographic route. Different surface plasmon resonance (SPR) modes focus consequently on their own positions due to the identical shape and uniform size and distance of these plasmonic metallic nanoparticles (Ag and Au). On the basis of this and FDTD (finite-difference time-domain) simulation, this work reveals the variation of all SPR parameters (position, intensity, width, and mode) with nanoparticle heights, which demonstrates that the effect of heights are different in various stages. On increasing the heights, the major dipole SPR mode precisely blue-shifts from the near-infrared to the visible region with intensity strengthening, a peak narrowing effect, and multipole modes excitation in the UV-vis range. The intensity of multipole modes can be manipulated to be equal to or even greater than the major dipole SPR mode. After coating conformal TiO2 shells on these nanoparticle arrays by atomic layer deposition, the strengthening of the SPR modes with increasing the heights results in the multiplying of the photocurrent (from ∼2.5 to a maximum 90 μA cm(-2)) in this plasmonic-metal-semiconductor-incorporated system. This simple but effective adjustment for all SPR parameters provides guidance for the future design of plasmonic metallic nanostructures, which is significant for SPR applications.

This work reports a nonlithographic nanopatterning approach to fabricate perfectly ordered nanoparticle arrays with tunable and uniform dimensions from about 30 to 80 nm and strict periods of 100 nm in a square lattice on large-area substrates by combining nanoimprinting with ultrathin alumina membrane technique. There is no requirement of any organic layer to support an ultrathin membrane in our novel route, which totally addressed the problems of nonuniform pores in prepatterned alumina templates and contamination during sample preparation, and thus is indispensable for our fabrication of ideally regular nanoparticle arrays on various kinds of substrates (such as flexible plastic). The effect of imprinted pressure on the prepatterning of Al foil was also studied in order to ensure the reusability of the precious imprinting stamps. This simple but efficient method provides a cost-effective platform for the fabrication of perfectly ordered nanostructures on substrates for various applications in nanotechnology.