Fabrication of large-area and long-range ordered nanostructures using template-assisted nanosphere self-assembly method

Large-area and long-range ordered monodisperse colloidal spheres in two-dimensional arrays have received a great deal of attention in recent year, and become a low cost and high throughput method in fabrication of 2D nanostructures. However, the prepared nanostructure by this method always has inevitable problems such as astable orientation in arrays, multilayered accumulations and lattice defects or cracks. These drawbacks of this method seriously affect the nanostructures in long-range order, which also gives poor repeatability and finally limits its performance in practical applications. In this paper, we proposed an improved way to try to overcome or reduce the influence effectively caused by the drawbacks above. The main idea is to use a patterned template to guide the process of nanosphere self-Assembly. In the method of gasliquid interface self-assembly, the structural boundary of the designed templates (as substrate) can exert a binding force on the colloidal spheres when they land on the templates' surface and begin to dewet. Our experiments show that, with the assistant of the templates, nanospheres are subjected to one or more of the binding force and can be tightly arranged on the substrate in a long-range order and in a controllable way. Comparing with the traditional way using bare substrate, our method can effectively reduce the lattice defects or cracks and also the regional double-layer accumulation. We also define two factors to evaluate the quality of the nanostructures fabricated by our method and show its advantages compare with the tradition way. This self-assembly method may have the potential application value in a wide range of fields such as optical communication, biochemical sensor, solar cells and so on.