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In this paper, we demonstrate a facile modified micromolding method to fabricate morphology-controlled elliptical hemisphere arrays (EHAs) by using stretched poly(dimethylsiloxane) (PDMS) nanowell arrays as molds. The PDMS nanowell arrays were fabricated via casting PDMS prepolymer onto two-dimensional (2D) non-close-packed (ncp) colloidal sphere arrays. By varying the stretching direction, stretching force, size of the colloidal spheres used and other experimental conditions in the fabrication process, we can control the shape, aspect ratio and size of the resulting microstructures. Moreover, our method does not involve any costly micromanufacture technique and can be applied to a great many materials, such as oil soluble polymers (e.g. polystyrene (PS)), water soluble polymers (e.g. poly(vinyl pyrrolidone) (PVP)), cross-linked polymers (e.g. photopolymerizable resin) and a variety of composites (e.g. polymer/nanoparticle composite). The anisotropic wetting properties of these EHAs were demonstrated. Potential application of the EHAs is to provide a model for the fundamental research of anisotropic surfaces and a template or mask for the fabrication of anisotropic surface patterns for potential applications of shape-dependent optical and magnetic devices.

We report a convenient method for the fabrication of ordered, binary patterned 2D (mdppy)BF arrays on the surface of gold substrates. Ordered arrays of water droplets formed in the hydrophilic regions of patterned self-assembled monolayers (SAMs) which consisted of isolated hydrophobic circles surrounded by a continuous hydrophilic region. Subsequent dewetting of (mdppy)BF solution in chloroform led to the formation of an ordered array of rings in the hydrophilic regions and an ordered array of circles in the hydrophobic regions. The former resulted from a surface-directed and concentration-controlled dewetting process, while the latter was a result of the selective wetting process. Dewetting structures could be controlled by changing the experimental conditions, such as the concentration of the (mdppy)BF solution and the water condensation process.