Fabrication of double nanohoneycombs (Al/SiO2) with controllable size using nanosphere lithography

The double nanohoneycombs (Al/SiO₂) on glass and Si substrates were fabricated by the two-step processes of nanosphere lithography (NSL). The working parameters of the fabrication processes were analyzed and the factors affecting the size of nano-homeycombs, such as controlling nanosphere size, lift-off nanosphere and the second NSL process were elucidated. In the first NSL process, an ordered single layer of polystyrene (PS) nanosphere with a diameter of 1000 nm was spin-coated on the substrates. Then, the PS nanospheres were modified by oxygen plasma works as deposition masks. By Al film deposition and lift-off processes, we fabricated ordered periodic nano-homeycombs (Al) arrays. After the second NSL process and SiO₂ film deposition, we fabricated ordered periodic double nanohomeycombs (Al/SiO₂) arrays. This technique forming double nanohoneycombs, especially with desired period, is expected to be a candidate for wide nanostructure applications such as photonic crystals, optoelectronic devices, sensors, data storage, fuel cells, etc.