Formation of textured Al thin film on silicone rubber to obtain superhydrophobic property

Abstract

Silicone rubber, which is widely used in electrical and biomedical applications, was modified into superhydrophobic property by the formation of a textured Al thin film on the periodic microswelling structure fabricated on silicone rubber by the 193 nm ArF excimer laser-induced photodissociation of silicone. The texturing of Al thin film occurred automatically during the vacuum evaporation only on the silicone rubber, compared with the cases of a slide glass or silicone resin substrate, which were observed by the scanning electron microscope and atomic force microscope. As a result, contact angle of water on the samples with 10- and 30-nm-thick, textured Al thin films was estimated to be approximately 162° in both cases, compared to the sample without Al of approximately 155°. Moreover, a large air gap was remarkably formed between the Al-deposited sample and water; a droplet of colored water was successfully confined in the air gap and it was released into the water when and where need.