A method to obtain vertically aligned silicon structures with a high aspect ratio, which are of the interest for the photovoltaics, using nanosphere lithography and cryogenic plasma etching was explored. For the conventional nanosphere lithography the etching of the latex spheres during the cryogenic plasma process limits the maximum ratio of Si wire length to the diameter at the level of 5/1. The maximum length of 2-3 μm could be obtained foe Si wires of 0.45 μm diameter. An intermediate step of SiO2 hard mask formation by nanosphere lithography was proposed to increase the maximum length. The nanosphere lithography with pre-deposit SiO2 layer allows on to increase the maximum length/diameter ratio to at least 15/1. An array of the Si wires of 0.45 μm diameter and length of 6 μm was obtained on entire surface of 4-inch Si wafers.