自然界中的蓮花葉面具有超疏水之特性，其接觸角約150˚、滑動角約5˚。其表面具能防水、自潔和流體滑動於界面之能力，可應用於玻璃清潔、太陽能電池、古蹟之保存、高樓、浴室及交通工具之清潔，而其滑動之邊界效應具應用於生物醫學方面之潛能。基於仿生學建立超疏水表面之結構，在近幾年引發極廣泛的基礎應用研究。然而該結構之結構強度低、大量複製困難，並易受外力受損失去自潔性的缺點。
本研究在於設計一不具奈米纖維之創新微結構，其與自然者大不相同。提出一種多層次之凹洞狀微結構，半封閉性反蓮花結構之PDMS，其接觸角大於165˚、滑動角小於10˚水滴可於微結構表面反彈。具彈性和超疏水之PDMS可清潔灰塵避免灰塵致太陽能電池效率的降低，提出此超疏水表面用於太陽能電池上的可行性。

In nature, leaves of Lotus are superhydrophobic surfaces. The contact angle is about 150° and slilding angle is below 5˚. The surfaces have the abilities of water-repellent, self-cleaning and slipping at the fluid-surface interface. Dominant applications can be found in the self-cleaning of glasses (window panes and windshields) and surfaces of solar cell, the protection of ancient remains, tall buildings, cars, bathrooms and structures in mountains. In addition, its slip boundary condition effect can potentially be applied in biomedicine. Based on the biomimicry, the study on creating super hydrophobic structures has triggered intense basic and applied research over the past several years. However, this kind of structures have some disadvantages, such as low structure strength and hard to replicate. It is easy to loss the ability of self-cleaning by the damage result from the external force.
In this study, we have to investigate an innovative novel superhydrophobic micro-structure without nano-fibers, a multi-leveled concaved structure of PDMS. This PDMS micro-structure showed an excellent water-repellent property with a contact angle higher than 165˚ and a sliding angle lower than 10˚. Droplets will rebound on the micro-structure of the surface. Such flexible and superhydrophobic surface showed a dust cleaning effect to prevent the degradation by dust particles of solar cell　and provides possibility of a practical application in solar cells.

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