Highly flexible, transparent and patternable parylene-C superhydrophobic films with high and low adhesion

This paper reports the first parylene-C based superhydrophobic films with high or low adhesion for potential droplet-based microfluidics. By creating hierarchical dual-scale micro/nanostructures and applying various plasma treatments, both biomimetic designs of lotus leaf effect with high contact angle and low adhesion, and petal effect with high contact angle but high adhesion, are demonstrated. Due to parylene´s properties, these superhydrophobic films are highly flexible and transparent. Moreover, selective patterning of hydrophilic and superhydrophobic areas on a single film is also achieved. The combination of flexibility, transparency, selective patterning and simple fabrication makes our superhydrophobic films compare favorably to other designs.