隨者半導體與微加工技術的進步，讓多種化學與生物的實驗流程整合單一
微型晶片上，相較於傳統的生化或生物分析，這種整合型具分析功能的晶
片或微型分析系統（Micro Total Analysis Systems, μTAS），僅需要
非常微小的液量即可平行處理大量的樣品與快速的分析，因此可以讓人們
得以更有效率的進行分子和細胞生物學研究；在這些微型分析系統中，細
胞和生物分子需藉流體進行混合或是輸送才得以進行相關的分析或是作
用，因此微流體在微型晶片系統中扮演非常重要的角色；傳統上利用微型
晶片系統是希望可以縮短檢測時間及費用，但是對於研究神經元系統的生
物學家而言，需要同時觀察神經元細胞的生長狀況及電生理訊號，進而了
解神經元網絡對於外來刺激的反應及生長狀況，然而目前可以同時進行活
細胞型態與電生理長期紀錄研究的微型晶片系統非常少；因此，本論文係
提出兩種結合光阻與氧化銦錫導電玻璃基板，製作可以同時進行型態觀察
及電生理訊號紀錄的多層微流道結構系統；其中一種係利用控制曝光時
間，決定每一層光阻固化的深度製作出多層結構，另外一種係利用犧牲
層的方法定義底層的結構，這兩種微流道系統皆具有導引及固定活細胞
在ITO電極的功能，並可同時對活細胞進行電生理訊號的紀錄及刺激；另
外，因為ITO玻璃基板是透明的，所以在進行電生理的研究同時，也可以
同步進行細胞型態的觀察。最後，透過斑馬魚紅血球與神經細胞的實驗，
說明所提出的設計結構有效的捕獲細胞並固定在ITO電極上，並且讓神經
細胞存活在光阻上至少14天證明其生物相容性，因此，證明所提出利用
光阻與ITO電極製作的多層結構的微流道系統，可以進行長時間的活細胞
培養，並可以同時進行型態觀察及電生理信號研究。

Contemporary semiconductor and micromachining technologies
have been exploited to develop lab-on-a-chip microsystems, which
enable parallel and efficient experiments in molecular and cellular biology. In these microlab systems, microfluidics play an important role for automatic transportation or immobilization of cells and bio-molecules, as well as for separation or mixing of different chemical reagents. However, seldom microlab systems allow both morphology and electrophysiology of living cells to be studied simultaneously for a long term. This kind of study is important, for example, for understanding how neuronal networks
grow in response to environmental stimuli. To fulfill this application need, this thesis investigates the possibility of fabricating multi-layer photoresists as microfluidic systems directly above a glass substrate with ITO electrodes. The microfluidic channels are designed to guide and trap living cells on top of ITO electrodes, through which the electrical activities of cells can be recorded or elicited. As both the microfluidic system and ITO electrodes are transparent, the cellular morphology is observable easily during electrophysiological studies. Two fabrication processes are proposed and compared. One defines the structure and curing depth of each photoresist layer simply by controlling the exposure time in lithography, while the other further utilizes a sacrificial layer to defines the structure of the bottom layer. The fabricated microfluidic system is proved bio-compatible and able to trap blood cells or neurons. Therefore, the proposed microsystem will be useful for studying cultured living cells efficiently in applications such as drug-screening.

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