Superhydrophobic polytetrafluoroethylene surface obtained using reactive ion etching and duplication with polydimethylsiloxane mould

The fabrication of a superhydrophobic surface by texturing of the polytetrafluoroethylene (PTFE) surface in the form of pyramidlike structures is demonstrated. In addition, the superhydrophobic surface is duplicated by using a polydimethylsiloxane (PDMS) mould. The hydrophobic properties were determined by measuring the contact angle and roughness of the PTFE surface on the pyramidal structure. The calculated roughness factor and root mean squares roughness ranged from 2.47 to 2.6 and 0.25 to 0.4 ?m, respectively. The contact angle of a water droplet on the PTFE surface was greater than 150, which was well maintained for over seven weeks. In the case of PDMS mould surface, the contact angle of a water droplet was greater than 130.