Zinc-oxide nanostructures are formed by forming a pattern on a surface of a substrate. A catalyst metal, such as nickel, is formed on the surface of the substrate. Growth of at least one zinc oxide nanostructure is induced on the catalyst metal substantially over the pattern on the surface of the substrate based on a vapor-liquid-solid technique. In one exemplary embodiment, inducing the growth of at least one zinc-oxide nanostructure induces growth of each zinc-oxide nanostructure substantially over a patterned polysilicon layer. In another exemplary embodiment, when growth of at least one zinc-oxide nanostructure is induced, each zinc-oxide nanostructure grows substantially over an etched silicon substrate layer.