本文針對目前產業技術的瓶頸–軟性基板從載台取下製程，作為研究方向，師法能夠在牆面上爬行的生物腳上黏著系統，發展仿生結構作為軟性基板與載台間的黏著介面。
基於表面黏著理論與破壞力學，在商用有限單元法軟體(COMSOL)中建構兩種數值模型，分析仿生結構的黏著力、應力分布與外型效應。文中提出三種不同的仿生結構外型分別為柱狀、柱狀且邊緣有導角、蘑菇狀。為了解決數值運算時所產生的無窮值與奇異值，LJ勢能函數(Lennard-Jones potential)被使用於處理表面分子間的作用力。另外從文獻中也確認JKR模型(Johnson-Kandall-Roberts model)適用於奈米尺寸(Nano-scale)與微米尺度(Micro-scale)間的中間尺度(Meso-scale)，該尺度符合本文所探討之仿生結構。其分析結果顯示結構黏著力隨著結構半徑變小而增加，並且蘑菇狀外型會有最強的黏著力；此外，也發現半漏斗狀的結構可增強結構強度，使仿生結構具有可重覆使用的特性。
除了建構數值模型，為了實際驗證仿生結構的黏著特性，本文採用奈米壓印技術製作仿生結構。由於奈米壓印需要一個模具使材料成型，因此利用放電加工、電鍍與雷射加工製作鎳鈷合金的模具，並透過模擬確認加工所需的參數。其結果顯示放電加工可製作出高密度的通孔陣列，透過電鍍可製作複雜的結構外型，例如漏斗狀。雷射加工因有熱傳效應使得結構間距必需維持在一定的距離，且該加工方法會造成表面不平滑。因此本文採用放電加工與電鍍製作模具。
最後使用模具在PEN表面製作仿生結構。因為PEN為熱塑性材料，熱轉印製程被使用於製作結構。透過加熱至玻璃轉換溫度以上，使材料處於熱融狀態，再施加壓力使材料填充入模具中。在填充的過程中，氣體會由通孔排出，不影響外型的轉移。降至室溫後，將模具脫離，即在PEN表面製作出仿生結構。為了確任該結構的黏著力，透過AFM探針量測測，可得知每個結構具有7 nN的黏著力。

Flexible electronics manufacturing faces a bottleneck in lift-off process. This dissertation proposed a possible solution for the challenge by means of constructing a biomimetic structure as adhesive intermediate of carrier and substrate.
Many insects possess evolved fibrillary structures on their feet to achieve extraordinary adhesion on vertical walls or ceilings. These fibrillary adhesive attachment systems consist of finely structured hairs with the size ranging from a few hundred nanometers to a few hundred micrometers, depending on the animal species. Learning from the fibrillary attachment systems of many insects, biomimetic structures were developed to achieve required adhesive characteristics herein.
This research designed appropriate biomimetic structures to be used in lift-off process of flexible electronics manufacturing by finite element method and surface adhesive theorem. The geometries of biomimetic structures were pillar, pillar with rounded edge, mushroom and half-hourglass. Surface adhesive theorem was based on theory of elasticity and micro mechanics. The theorem of contact between a sphere and an elastic half-space were used to find contact area and adhesive force, and the shape effect was investigated by using JKR model and Lennard-Jones Potential. In lift-off process, tensile force and crack force between biomimetic structure and elastic substrate were calculated by Griffith condition. By varying relative peel angles, functional variables were built to estimate peeling process of adhesive structure in various conditions. The results show that the finer contact structures give rise to higher adhesion force. The mushroom-shaped tip enhances more adhesive force while the flat shape with rounded edge has the least adhesive force. The half-hourglass structure featuring a larger base can decrease the stress concentration at the bottom of the structure, so that the failure during the peeling process can be avoided.
According to the results of simulation, the mold was made of nickel-cobalt alloy by three methods, including electrical discharge machining, electroforming and laser machining. The PEN was filled into the mold by nanoimprint and the adhesive forces of the structures were estimated by AFM.

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