Gecko Hair Fabrication
Synthetic Gecko Hair Fabrication by DRIE + Molding methods.

Introduction: Mushroom shape micro and nano polymer structures can be produced using DRIE (Deep Reactive Ion Etch). Using Champagne Glass Effect on thin oxide layer of SOI (Silicon on Insulator) wafer with DRIE, we are able to create mushroom shape micro/nano scale fiber master template. With this template, micro/nano polymer fiber array can be fabricated by subsequent molding in a large area.

Approach: The team already developed the methods for the fabrication of mushroom shape microfibers and is currently developing and testing methods for the production of polymer nanofibers and micro/nano hierarchical fibers. Using standard DRIE technology and commonly available equipment in clean room, arrays of super uniform mushroom shape micro/nana fibers can be constructed.

Benefits: DRIE is one of the well defined microfabrication methods to generate highly uniform high aspect ratio trench. CGE (Champagne Glass Effect) of DRIE allows us to fabricate mushroom shape fiber array negative template. DRIE and CGE natively do not have any limit to fabricate the negative mold for nanoscale mushroom shape fibers.

Members: Jiho Song

Past Members: Seok Kim, Metin Sitti

Papers:

• R. Long, C.-Y. Hui, S. Kim, and M. Sitti, "Modeling the Soft Backing Layer Thickness Effect on Adhesion of Elastic Microfiber Arrays," Journal of Applied Physics, 2008, in press.
• S. Kim, B. Aksak, and M. Sitti, "Enhanced friction of elastomer microfiber adhesives with spatulate tips," Applied Physics Letters, vol. 91, pp. 221913, 2007.
• S. Kim, M. Sitti, C.-Y. Hui, and R. Long, A. Jagota, "Effect of backing layer thickness on adhesion of single-level elastomer fiber arrays," Applied Physics Letters, vol. 91, pp. 161905, 2007.
• S. Kim and M. Sitti, "Biologically inspired polymer microfibers with spatulate tips as repeatable fibrillar adhesives," Applied Physics Letters, vol. 89, pp. 261911, 2006. (Selected among Core 15 Papers for Thomson Scientific's Fast Moving Front Map of Materials Science, Jan. 2008)
• S. Kim, J.-H. Jang, M. Sitti, and E. Thomas, "Fabrication of gecko foot inspired elastomer nanofibers with spatulate tips," IEEE Nanotechnology, 2008, to appear.
• S. Kim, and M. Sitti, "Fabrication and characterization of biologically inspired mushroom-shaped elastomer microfiber arrays," ASME IDETC Micro/Nano Systems, 2008, to appear.
• S. Kim and M. Sitti, "Fabrication and characterization of biologically Inspired microfiber arrays with spatulate tips," International Conference on Micromanufacturing, 2008, to appear.