화학공학소재연구정보센터
Journal of Adhesion Science and Technology, Vol.22, No.15, 1967-1983, 2008
Generation and Characterization of Super-Hydrophobic Micro- and Nano-structured Surfaces
Here we describe the use of a backside exposure method for the creation of high aspect ratio tapered microstructures with nano-porous sidewalls. These sidewalls result from the exposure and curing conditions of the SU8 matrix. The structures show ultra-hydrophobic behavior with water contact angles of more than 160 degrees, without an additional coating of the SU8 polymer. By choosing appropriate exposure conditions, needle-like structures can be created with a high level of porosity, covering their entire surface. The contact angle hysteresis values of such structures lie in the range of 20 degrees. After an additional deposition of smooth and thin metallic gold film and coating it with an alkyl thiol self-assembled monolayer (SAM), we were able to decrease this hysteresis to values of around 10 degrees. By using thin and rough metallic films like wet chemically oxidized titanium oxide and a fluoralkylsilane SAM, the hysteresis values could be reduced to only 4 degrees. (c) Koninklijke Brill NV, Leiden, 2008