| 초록 |
In the process of creating self-cleaning and anti-biofouling surfaces, the ability of the surface to surface to repel liquids plays a crticial role. Surface in nature achieve hydrophobicity induced by micro or nano bumps coverd with materials with low surface energy. Also, super-lattice strucures composed of hexagonal ridge of pillar structure are known to show high resistance at elevated pressure such as springtail cuticles. To fabricate artificial hydrophobic surfaces, many researcher found that the periodic ridge structures on springtail cuticle form capillary liquid pinning bridges, which enhance pressure resistance. Inspired by the natural surfaces, we fabricated the artificial super-lattice strutures that contain hexagonal periodic ridge structures using phase shift lithography and Moiré effect. We observe that artificial hexagonal ridge structures enhance the surface hydrophobicity. In further study, we study about the effect of ridge dimensions on wetting property. We can control the hexagon density using Moiré effect. The high hexagon density enhances the hydrophobicity at same surface roughness. The result shows that the prestigious wetting equation(Wenzel or Cassie)is not always correct at wetting researches. We conclude that super-lattice structures affect the surface wetting property and contact angle is determined by interaction between surface and droplet contact line. |
