Controllable Fabrication of Patterned Oblique Nanowire Array and Its Application as a Reflection Grating

Aligned oblique nanostructures are widespread and playing important roles in natural world. However the controllable fabrication of these nanostructures is still a challenge up to now. Here we developed a simple silica nanopsheres assisted ion bombarding method to make patterned oblique nanowire (NW) arrays on different substrates such as polyimide (Kapton) film, polyester (PET) film, polyaniline (PANI) film and SU-8 photoresist film. Their obliquity, diameter, wire density and length were well controlled by changing the experimental parameters. By changing the incident angle of Ar+ ion beam, NW arrays with oblique angles ranging from 20 degrees to 80 degrees were made, and oblique NW arrays with diameters ranging from 191 to 331 nm were fabricated using different sized silica nanospheres as shadow mask. The density of the silica nanosphere array determined the wire density of the oblique NW array. The bombarding time by Ar+ ions was used to control the length of the NW. Finally, the aligned oblique NW array was made into a reflection grating, which showed anisotropic structural color.