Liquid-bridging in particle self-assemblies toward constructing periodic nano-mesh structures and nano-dot arrays

We demonstrate a simple generic principle of constructing periodic nano-mesh structures and nano-dot arrays by liquid-bridging in particle self-assemblies. A self-assembly of nano- to micro-sized spheres of polystyrene, produced in a close-packed monolayer on a substrate by a convective method, is used as a template for liquid-bridging of a functional fluid in the pores among the neighboring particles. After the solidification of the fluid, followed by the detachment of the particles from the substrate, a periodic mesh structure is directly obtained. Moreover, deposition of a desired substance onto such mesh structure made of a sacrificial material, which is subsequently removable through a lift-off process, enables to produce a periodic dot array of the substance. Depending on the size of the particle and the nature of liquid bridging in the particle assembly, a variety of nano-mesh structures of silver-ink and nano-dot arrays of gold are constructed. This simple liquid bridging-based methodology is easily applicable for different classes of functional fluids such as soluble organic semiconductors.