Sub-100-nm nanoparticle arrays with perfect ordering and tunable and uniform dimensions fabricated by combining nanoimprinting with ultrathin alumina membrane technique.

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.