本文透過從大自然中獲取的靈感，以壁虎腳上的特殊微結構作為研究目標，期望可以做出類似結構，並同樣產生黏著效應，針對目前產業技術的困境–軟性基板從載台取下製程，作為軟性基板與載臺間的黏著介面。
本文最主要的重點，在於將PDMS摻雜磁性顆粒，製作出具有可控的黏著性表面，並提供有效磁場，試圖改變微結構角度，以達到控制黏著力的大小，可以做為創新的吸附工具。
本文依據表面黏著理論，透過相關的數值模型，分析仿生結構的黏著力、應力分布與外型效應，設計微結構的整體相關參數，試圖找出具有最佳黏著效應的微結構表面，並透過實驗驗證之。
本文採用壓印方式製作微結構，因此需要模具使材料成型，所以利用微影蝕刻的方式製作矽模具，並與本實驗室洪志毅學長製作的鎳鈷合金模具進行比較，最後使用PDMS分別對兩種模具進行壓印，製作出微結構並進行量測，比較其差異。

Inspired by Gecko effect, which the surface of Gecko toe pads has many micro/nano-structures for generating adsorption forces to provide strong and reversible attachment to surfaces of varying topography, this study is intended to facilitate the peeling-off process by design of a type of biomimetic adhesive structure on the surface of flat solid carrier. The peeling-off process serves as the last step of manufacturing flexible electronics, which lifts the flexible film from the solid substrate.
The purpose of this paper is to design and fabricate a type of controllable adhesive microstructure on the surface of a substrate. This is accomplished by doping magnetic nanoparticles into PDMS, and then providing an effective magnetic field to change the angle of microstructure to achieve the desired controllable adhesion. Consequently, the surface adhesion theory is used to analyze the adhesion, stress distribution and the effect of the appearance of the microstructure through the relevant numerical models. Parametric design is performed which is validated by experiment.
Herein imprinting process with two types of molds is used to make the microstructures, which include a fabricated by lithography and dry etching and a metallic mold made by electrical discharge method. Finally, the microstructures made from PDMS were fabricated and the controllability of the adhesive is measured.

[1] Karl Amundson et al. Flexible, active-matrix display constructed using a microencapsulated electrophoretic material and an organic-semiconductor-based backplane. SID International Symposium Digest of Technical Papers 32, 160 (2001).
[2] P. Drzaic et al. A printed and rollable bistable electronic display. SID International Symposium Digest of Technical Papers 29, 1131 (1998).
[3] Tod Schneider et al. Flexible encapsulated cholesteric LCDs by polymerization induced phase separation.SID International Symposium Digest of Technical Papers 36, 1568 (2005).
[4] Tang CW and VanSlyke SA. Organic electroluminescent diodes. Applied Physics Letters 51, 913 (1987).
[5] 工業技術研究院, “微形變壓阻感測技術”, http://www.itri.org.tw/chi/focus/focus_detail.asp?RootNodeId=010& NodeId=010&FocusNewsNBR=83。
[6] 工業技術研究院, “可撓式微型陣列超音波換能器技術”, http://www.itri.org.tw/chi/tech-transfer/04.asp? Root NodeId=040&NodeId=041&id=3562。
[7] Junji Kido et al. Multilayer White light-emitting organic electroluminescent Device. Science 267, 1332(1995).
[8] Brian O’Regan and Michael Gratzel. A low-cost, high-efficiency solar cell based on dye-sensitizedcolloidal Tio2 films. Nature 353, 737 (1991).
[9] Through Silicon Technologies, “Through-silicon-vias” available on the website:http://www.trusi.com/frames.asp?5 (Access date: Dec. 4, 2007)
[10] D.R. Cairns et al. Strain-dependent electrical resistance of Tin-doped Indium Oxide on polymersubstrate. Appl. Phys. Lett. 76, 1425 (2000).
[11] Boyeon Sim et al. Highly enhanced mechanical stability of indium tin oxide film with a thin Al bufferlayer deposited on plastic substrate. Surface & Coatings Technology 204, 309 (2009).
[12] Marmur. The lotus effect: Superhydrophobicity and metasatbility. Langmuir 20, 3517 (2004).
[13] S. Zschokke. Spider-web silk from the early cretaceous. Nature, 424, 636 (2003).
[14] H. Gao et al. Mechanics of hierarchical adhesion structures of geckos. Mech. Master. 37, 275 (2005).
[15] P. Maderson. Keratinized epidermal derivatives as an aid to climbing in gekkonid lizards. Nature 203,780 (1954).
[16] W.F. Dellit. Zur anatomie und physiologie der Geckozehe. Jena. Z.Nature, 68613 (1934).
[17] K. Autumn et al. Adhesive force of a single gecko foot-hair. Nature 405, 681 (2000).
[18] K. Autumn et al. Evidence for van der waals adhesion in gecko setae. Proc Natl Acad Sci USA 99,12252 (2002).
[19] G. Huber et al. Evidence for capillarity contributions to gecko adhesion from single spatulananomechanical measurements. PNAS 102, 16293 (2005).
[20] W. Sun et al. The nature of the gecko lizard adhesive force. Biophys J. 89, L14 (2005).
[21] P. Niewiarowski et al. Sticky gecko feet: The role of temperature and humidity. PLoS one 3, e2192(2008).
[22] A. K. Geim et al. Microfabricated adhesive mimicking gecko foot-hair. Nat. Mater. 2, 461 (2003).
[23] M. Jin et al. Superhydrophobic aligned polystyrene nanotube films with high adhesive force. Adv. Mater.17, 1977 (2005).
[24] D. Kim et al. Replication of high-aspect-ratio nanopillar array for biomimetic gecko foot-hair prototypeby uv nano embossing with anodic aluminum oxide mold. Microsyst Technol 13, 601 (2007).
[25] Y. Tsai et al.E-beam photoresist and carbon nanotube as biomimetic dry adhesives. 19th IEEEInternational Conference on Micro Electro Mechanical Systems, 926 (2006).
[26] H. Jeong et al. Stretched polymer nanohairs by nanodrawing. Nano Lett. 6, 1508 (2006).
[27] E. Yoon et al. Tribological properties of bio-mimetic nano-patterned polymeric surfaces on silicon wafer.Tribology Letters 21, 31 (2006).
[28] Y. Zhao et al. Interfacial energy and strength of multiwalled-carbon-nanotube-based dry adhesive. J. Vac.Sci. Technol. B 24, 331 (2006).
[29] B. Yurdumakan et al. Synthetic gecko foot-hairs from multiwalled carbon nanotubes. Chem. Commun.30, 3799 (2005).
[30] L. Ge et al. Carbon nanotube-based synthetic gecko tapes. PNAS 104, 10792 (2007).
[31] C. Majidi et al. High friction from a stiff polymer using microfiber arrays. Phys. Rev. Lett. 97, 4 (2006).
[32] C. S. Majidi et al. Attachment of fiber array adhesive through side contact. J. Appl. Phys. 98, 103521
[33] J. Lee et al. Sliding-induces adhesion of stiff polymer microfiber arrays. i. macroscale behavior. Journalof The Royal Society Interface 5, 835 (2008).
[34] M. Northen and K. Turner. Meso-scale adhesion testing of integrated micro- and nano-scale structures.Sensors and Actuators A: Physical 130-131, 583 (2006).
[35] M. Murphy et al. Enhanced adhesion by gecko-inspired hierarchical fibrillar adhesives. ACS AppliedMaterials & Interfaces 1, 849 (2009).
[36] H. E. Jeong et al. A nontransferring dry adhesive with hierarchical polymer nanohairs. PNAS 106, 5639(2009).
[37] J. Lee et al. Gecko-inspired combined lamellar and nanofibrillar array for adhesion on nonplanar surface.Langmuir 25, 12449 (2009).
[38] Z. Dai et al. Adhesion characteristics of polyurethane for bionic hairy foot. Journal of IntelligentMaterial Systems and Structures 17, 737 (2006).
[39] D. Santos et al. Directional adhesion for climbing: theoretical and practical considerations. Journal ofAdhesion Science and Technology 21, 1317 (2007).
[40] S. Kim et al. Whole body adhesion: hierarchical, directional and distributed control of adhesive forcesfor a climbing robot. IEEE International Conference on Robotics and Automation, 1268 (2007).
[41] S. Kim et al. Smooth vertical surface climbing with directional adhesion. IEEE Transactions on Robotics24, 65 (2008).
[42] S. Gorb et al. Biomimetic mushroom-shaped fibrillar adhesive microstructure. Journal of The royalSocity Interface 4, 271 (2006).
[43] H.Gao et al. Shape insensitive optimal adhesion of nanoscale fibrillar structures. PNAS 101, 7851(2004).
[44] A. del Campo et al. Contact shape controls adhesion of bioinspired fibrillar surfaces. Langmuir 23,10235 (2007).
[45] S. Kim and M. Sitti. Biologically inspired polymer microfibers with spatulate tips as repeatable fibrillaradhesives. Appl. Phys. Lett. 89, 261911 (2006).
[46] P. Michael et al. Gecko-Inspired directional and controllable adhesion. Small 5, 170 (2008).
[47] P. Lin et al. Mechanically tunable dry adhesive from wrinkled elastomers. Soft Matter 4, 1830 (2008).
[48] A. G. Gillies et al. Controllable particle adhesion with a magnetically actuated synthetic gecko adhesive.Adv. Funct. Mater 23, 3256 (2013).
[49] H. Yoon et al. Adhesion hysteresis of janus nanopillars fabricated by nanomolding and oblique metaldeposition. Nano Today 4, 385 (2009).
[50] H. E. Jeong et al. Stretchable, adhesion-tunable dry adhesive by surface wrinkling. Langmuir 26, 2223(2010)
[51] S. Reddy et al. Bioinspired surfaces with switchable adhesion. Adv. Mater 19, 3833 (2007).
[52] J. Krahn et al. Magnetic field switchable dry adhesives. Appl. Mater. Interfaces 7, 2214 (2015).
[53] 洪志毅,” Smart biomimetic structure applied to flexible
substrate lift-off process,” 國立清華大學動力機械系博士論文(2017)
[54] K. L. Johnson, “Contact Mechanics,” Cambridge University Press, London (1985).
[55] K. L. Johnson, K. Kendall, and A. D. Roberts, “Surface Energy and the Contact of Elastic Body,” Proc.Roy. Soc. London. A., Vol. 324, pp.301-313(1971).
[56] B. V. Derjaguin, V. M. Muller, and Y. P. Toporov, “Effect of Contact Deformations on the Adhesion of Particles,” J. Colloid Interface Sci., Vol.53, pp.314-326(1975).
[57] D. Tabor, “Surface Forces and Surface Interactions,” J. Colloid Interface Sci., Vol.58, No. 1 (1977).
[58] D. Maugis, “Adhesion of Spheres: The JKR-DMT Transition Using a DugdaleModel,” J. Colloid Interface Sci., Vol. 150, pp.243-269(1992).
[59] J. A. Greenwood, Proc. Roy. Soc. London A, “Theory of adhesion: Role of surface roughness,”Vol. 453, 1277-1297(1997).
[60] K. L. Johnson, and J. A. Greenwood, “An Adhesion Map for the Contact of Elastic Spheres,” J. Colloid Interface Sci., Vol. 150, pp.326-333(1997).
[61] B. Bhushan, “Handbook of Micro/Nano Tribology,” 2nd Ed., CRC Press, Boca Raton(1995).
[62] Ye Tian, Zizhou Zhao, Gina Zaghi, Yongkwan Kim, Dongxing Zhang, and Roya Maboudian ,”Tuning the Friction Characteristics of Gecko-Inspired Polydimethylsiloxane Micropillar Arrays by Embedding Fe3O4 and SiO2Particles”, ACS Appl. Mater. Interfaces, 7 (24), pp.13232–13237(2015).
[63] J P Díaz Téllez, S Harirchian-Saei, Y Li and C Menon,” Adhesion Enhancement of Biomimetic Dry Adhesives by Nanoparticle in Situ Synthesis” Smart. Mater. Struct, 22, 105031(2013)