近年來，由於許多科技和製程技術都已經發展成熟，因此利用微機電技術的元件去對生物分子做操控與分析的研究也正日漸增多，已成為生物科技上ㄧ項重要的領域。其目的是將許多功能整合成一個實驗室晶片 (Lab-On-a-Chip)作為全功能性的疾病檢測與分析晶片。目前已經有許多的技術被發表提出，像是：微鑷夾 (Microgripper )和微過濾器 (Micro Filter)…等等，但是這些都有一些嚴重的缺點和侷限。因此，我們致力於發展出一個簡單又可以大量有效率地分離細胞之生醫晶片。
在本篇論文中，我們利用光鑷夾 (optical tweezers) 配合微流體管道與介電泳 (Dielectrophoresis) 所設計之生醫晶片去對細胞產生分類的效果。利用微流體的性質在流道中形成穩定的層流與加上許多的分支流道達到流體減速的目的。再施加特定範圍頻率的電壓於設計的微電極上，對細胞產生負介電泳力，達到細胞偏移 (deflection) 和抬升 (levitation)的效果，能更有效率地分離細胞。接著，利用全像光鑷夾 (holographic optical tweezers) 所產生的線形雷射光去做細胞分離的效果。
其中先以模擬軟體CFDRC 分析與驗證設計概念後，再將整體的設計以微機電製程技術實現。實驗結果利用聚苯乙烯 (Polystyrene) 微粒子代替細胞驗證此生醫晶片的功效與可行性。

Recently, researches about manipulation and analysis of bio-particles by MEMS devices are increasingly growing because of technology and fabrication development. It becomes an important field of bio-technology. Its purpose is to integrate many functions into a Lab-On-a-Chip system for full functional disease detection and analysis. Today, there are many technology have been presented, such as: microgripper, micro filter and etc. But each of them has some critical drawbacks and restrictions. Therefore, we aim at developing a bio-chip which could separate large numbers of cells easily and efficiently.
In this thesis, we utilize optical tweezers combining a bio-chip designed with micro channels and DEP (dielectrophoresis) to sort cells. It is a laminar flow in the microchannel. We add many side-channels for deceleration. By applying input AC voltage within specific frequency range on the micro electrodes, cells could be deflected and levitated in our device to sort much efficiently. Later, we use linear optical pattern generated by holographic optical tweezers to separate cells.
First of all, through numerical simulation software CFDRC, the design concepts are verified and then realized by MEMS fabrication process. Finally, we use polystyrene beads in place of cells to demonstrate the feasibility and the functions of this bio-chip.

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