在本研究中已在超疏水的仿生荷葉表面上達成可回復式之電濕潤,超疏水結構中的微米結構是由厚膜光阻AZ-9260所構成的,而其中奈米結構是由覆蓋在微米表面的parylene以反應式離子蝕刻過後所形成的,這兩種結構所形成的複合結構表面對於去離子水的接觸角及遲滯角大約為160度及3度,然而當只有奈米或微米結構時,其遲滯角將變得非常大,此時的表面並沒有辦法應用於可回復式之電濕潤

開放式之電濕潤晶片將比傳統之電濕潤晶片在設計及檢測上多了更多的彈性,本研究的開始式電濕潤晶片可以在38V下成功的驅動7ul的液珠

在本研究中,以奈米及微米結構所形成的複合結構取代EWOD晶片上的疏水層,以達成可回復式之電濕潤,因為此複合結構表面有三個不同的能階,所以當施加特定電壓時,該表面還是可以維持低遲滯的狀況,所以可以在該表面達成可回復式之電濕潤,在驅動晶片部分,此EWOD晶片的表面特性最多可承受160V的直流電,而還是維持低遲滯的特性,而接觸角最多可改變大約14度左右,不過,一但電壓超過160V,將造成該表面之永久性的傷害

Reversible electrowetting on super-hydrophobic lotus leaf mimetic surface has been demonstrated in this research.
Well-designed patterned thick photo resist AZ-9260 is for micro structures. Therefore, a thin parylene film is deposited and etched to form nano structures on micro structures. The hydrophobicity and hysteresis of the binary structures are about 160° and 3° by contact angle. However, if there are only micro or nano structures, the hysteresis of the hydrophobic surface will increase tremendously.
By removing the cover electrode from traditional EWOD, the chip has more flexibility on designing and sensing. This EWOD chip successfully demonstrates the droplet (about 7 μl) movement by applying a voltage 38 V.
In this research, the super-hydrophobic lotus leaf mimetic structures are substituted for Teflon on EWOD chip. The structures have three energy barriers, so the surface can keep small hysteresis and water contact angle is reversible after applying a specific voltage. The maximum contact angle difference is about 14° with a voltage 160 V. However, the reversibility of the surface will be failed if a voltage over 160 V is applied.

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