微液滴驅動之研究與探討

Studies of actuation on micro liquid droplets

張日謙(Jih-Chien Chang)

指導教授 ： 楊宗勳

國立中央大學/理學院/光電科學研究所/碩士(2006年)

摘要

傳統上EWOD元件容易發生水解或膜破的缺陷，其原因為過高的電壓操作或是不穩固的疏水層所造成，因此本文提出了三個解決方案：1.採用高介電質材料二氧化鈦或五氧化二鉭做為介電層，以降低操作電壓。2.採用新型疏水材料Cytop?，以得到更穩固的疏水層。3.利用交流電訊號做為驅動電壓來源，透過DEP介電泳效應及表面張力原理的雙重影響，使得液滴在更低的電壓條件下獲得更大的驅動力。透過結構的改進，得到更穩定的EWOD微液滴操控平台。

　　另一方面，本文利用虛擬儀控軟體LabVIEW設計人機介面，加上放大電路及操控電路的應用，成功地以全自動的方式來驅動EWOD元件上的滴液，並且透過全自動EWOD微液滴驅動系統做光學方面的應用，利用液滴的來回震盪，將雷射光束於水平軸上偏折至不同的方向，以達到光束掃描的效果。

關鍵字

鐵氟龍 ； 介電質電濕式 ； 微滴體

並列摘要

This thesis reports three solutions to improve the defects, hydrophobic layer broken and electrolysis occurred easily, of a conventional electrowetting on dielectric (EWOD) Microfluidic system. These defects caused of high voltage applied and the hydrophobic material is not stable. First, the applied voltage could be decreased by using high dielectric material TiO2 or Ta2O5 to be dielectric layer. Second, we used Cytop? to be the new and stable material of hydrophobic layer. Third, we changed the power source from DC voltage into AC, let liquid gets more thrusting power. The microfluidic system is more stable by using these three improved methods.

By the way, the automatic EWOD Microfluidic system was developed by using graphical development software Labview, voltage amplifier and a relay based circuit. In application, the scanning system which is based on optical refracting theorem was also discussed. The light beam would be refracted into different ways, depending on the harmonic motion of droplet.

並列關鍵字

micro liquid droplets ； EWOD ； Teflon

參考文獻

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