Fabrication of superhydrophobic surfaces with controlled topography and chemistry

We report the fabrication of sub-micrometer large silicon pillars with controlled aspect ratios by combining thin polymer film structuring and dry etching. A wide library of structures was achieved thanks to the tunability of the process both concerning lateral and vertical dimensions. The structures were further used to create superhydrophobic surfaces. Depending on the aspect ratio of the pillars, different superhydrophobic wetting states were observed. Special attention was also paid to the influence of surface structuring on the contact angle hysteresis.