Berlin 2012 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

O: Fachverband Oberflächenphysik

O 47: [DS] Micro- and nanopatterning (jointly with O)

O 47.7: Vortrag

Mittwoch, 28. März 2012, 13:15–13:30, H 0111

Rapid Prototyping of Hierarchical Gecko-Mimicking Nano- and Microstructures using Multiphoton Absorption — •Michael Röhrig¹, Michael Thiel², Matthias Worgull¹, and Hendrik Hölscher¹ — ¹Karlsruhe Institute of Technology, P.O. Box 3640, 76021 Karlsruhe, Germany — ²Nanoscribe GmbH, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopolds., Germany

Applying 3D direct laser writing, we designed hierarchical gecko-type structures which match the elastic modulus and the relevant length scale of the gecko's setae very closely. These setae, delicate hairs covering the gecko's toes, originate the famous ability of geckos to climb effortlessly walls and ceilings. The setae are consisting of beta-keratine, a stiff material with Young's modulus of around 1 - 4 GPa. Due to their hierarchical design, they are very compliant and can achieve a very high real contact area even to rough substrates. Thus, the van der Waals forces cause high adhesion that enables geckos to stick to nearly every surface. Mimicking the gecko-effect is therefore pursued by groups all over the world. However, such structures are mostly based on soft materials that usually have some drawbacks, like degradation or rapid contamination. Hence, we used 3D direct laser writing to structure stiff materials. 3D direct laser writing is a rapid prototyping method based on multiphoton absorption that allows for the fabrication of arbitrary three-dimensional structures down to the nanometer scale. Measuring the adhesion by using atomic force microscopy, we could show that hierarchy is indeed favorable for artificial gecko-inspired structures made of stiff materials on the nanometer scale.