鏡像介電濕潤之液滴法研究並應用於平行微液滴操控

Abstract

介電濕潤（Electrowetting-on-dielectric，EWOD）是一種以施加電壓改變電極上介電層表面濕潤特性之現象，介電濕潤由於其所耗功率極低，可反覆變化表面疏水性及親水性，製作簡單且成本低。鏡像介電濕潤(Mirror-EWOD)則是以液態電極取代傳統的固態電極，當液體電極與介電薄膜上之微液滴體積相當時，介電濕潤現象同時再上下兩微液滴上發生，且雙液滴會發生自我對準的現象。本論文以多組實驗數據去分析鏡像對稱介電濕潤現象，並將整個裝置至於矽油中，減少液滴在空氣中震動與蒸發的問題。最後結合介電濕潤（EWOD）以及鏡像介電濕潤（MEWOD）技術，當施加適當電壓時，雙微液滴可同時被操控於數位微流體晶片，而驅動方式與傳統晶片相同，當增加介電薄膜數目時，在不需增加製程與驅動電路複雜性之情況下則可驅動多微液滴。

EWOD (Electrowetting-on-dielectric) is a method to change the surface wettability on top of an electrode. This phenomenon is reversible and consumes very low power. MEWOD (Mirror-EWOD) is occurred when we replace solid electrode with liquid electrode, and the size of the liquid electrode is shrunk to a comparable volume of the upper droplet. Electrowetting was found on both sides of the dielectric film and the mirror-EWOD force would bring the overlapped droplets to each other. In this thesis, we analyze the phenomenon of MEWOD and put the device into silicone oil to reduce the problem of vibration and evaporation. Finally, we integrate EWOD and MEWOD to manipulate parallel droplets. When applying a voltage, two stacked droplets can be actuated concurrently. By increasing the number of the dielectric sheet, the concept would be expanded to manipulate more than two droplets without increasing the complicity of the device fabrication and the electric circuit.