Super-hydrophobic properties have been achieved on the rf-sputtered polytetrafluoroethylene(PTFE) films deposited on etched aluminum surfaces. The microstructural evolution created after etching has been investigated by FESEM. The water contact angle over 160o can be achieved on the rf-sputtered ultra-tihn PTFE film less than 10 nm coated on aluminum surface etched with 7 wt.%, 12.5 wt.%, and 15 wt.% HCl concentration for 12 min. XPS analysis have revealed the presence of a large quantity of -CF3 and -CF2 groups in the rf-sputtered PTFE films that effectively can reduce the surface energy of etched aluminum. The presence of patterned morphology along with the low surface energy at the rf-sputtered PTFE coating makes the aluminum surface with high super-hydrophobic property.
