Morphology-controlled fabrication of elliptical nanoring arrays based on facile colloidal lithography

Abstract

In this paper, we demonstrate a facile modified colloidal lithography (CL) method for the fabrication of morphology-controlled elliptical nanoring arrays (ERAs), which combines template-guided dewetting of polymer film and oxygen reactive ion etching. The elliptical templates were fabricated via a modified micromolding method using colloidal nanosphere arrays as the original templates, which were used to guide the dewetting of the polymer film to form ERAs. The height, aspect ratio and size of the resulting arrays could be controlled exactly. Moreover, through etching the underlying functional materials or mixing functional materials into the polymer film, elliptical ring arrays of different functional materials could also be fabricated, such as gold ERAs, silicon ERAs, ferromagnetic Fe–Ni composite ERAs, Fe3O4 ERAs and fluorescent ERAs. A potential application of the as-prepared functional ERAs is to provide a model for the fundamental research of anisotropic properties of the asymmetric patterned surface arrays and the fabrication of anisotropic surface pattern based devices for potential applications of shape-dependent optical and magnetic devices.