近來，利用微機電技術製作的生醫晶片(Biochip)以及檢測型微流體系統晶片，在臨床診斷、醫療檢測上愈發扮演重要的角色。然而，微流體系統晶片的製作除了生化知識外，搭配微機電製造技術，將可大幅提升其性能，強化自動化功能，減少人為操作檢測造成的污染及誤差。因此，微幫浦的設計更是微流體晶片上不可或缺的一環，它是輸送流體的動力來源，主要具有輸送微量樣品的功用以及控制樣品的流向，其發展已有多年之久。目前，為了應用於生醫晶片以及各種檢測型微流體系統晶片上，正朝向一種能達到低耗能、低驅動電壓以及室温操作之微幫浦來發展。但由文獻回顧可知，可動件式的微幫浦，如靜電式、壓電式，較複雜且非半導體製程相符合會使得微流體的成本增加，而電解氣泡方式是最為符合此三要件之驅動器，另外在微流體切換器方面，微閥門需要較復雜的結構抑或是外接式驅動器的設計，大幅減少微流體元件的攜帶性。本文將介紹一種新型電解氣泡驅動式微流體幫浦，藉由與介電溼潤法在微流道之中當作閥門使用，以便達成具有微流體切換器功能的幫浦，以改善目前的微流體元件的缺點為目標，以發展適合可攜式微流體晶片。目前的幫浦初步結果達到每次循環需花費十秒並且有15nl 的純水可被推進，在未來合理的預估情況，假設能做多次的循環，每分可達90nl的流量.

In this thesis, the electrolysis-bubble-actuated micropump which takes advantage of EWOD (Electrowetting-on-Dielectric) to approach the feature of 1xN microfluidic switches is reported. With the time-sequence power control, the microfluid can be transported by using the electrolysis-bubble actuation and directionally controlled by tuning the surface property of the microchannels via EWOD. The advantages of this proposed micropump design not only achieve a net pumping flow but also integrate the switch function without the drawbacks that exist in the early reported micropumps and microfluidic switches, such as the complicated moving valves, large/long nozzle-diffuser structure, and high power consumption. Here we describe the design, operation principle and preliminary results of this micropump. Micropumps and microfluidic switches have a variety of applications. Many mechanisms and designs have been reported for the development of micropump and micro flow switches. Among them, electrolytic-bubble actuation is one of those mechanisms to pump micro flow moving forward. However, few microfluid systems take advantage of embedded micropumps for microfluidic switches. In this research, we focus on the development of hybrid functional microfluidic components, the switchable micropumps, which are capable of precisely pumping and dispensing continuous fluid sample into the desired reservoirs. The maximum pumping volume of one cycle is about 15nl. It takes 10 seconds to finish whole process. For the reasonable estimation in our design, the maximum pumping flow rate of this pump is 90nl/min.

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