微混合器是實驗室晶片中重要的元件，依據其驅動方式分為主動式與被動式兩種。其中被動式混合器的優點主要在於製程簡單且容易整合其它元件。若其能進一步以毛細力達到流體自驅動，將能夠免除晶片內外幫浦的使用，並使實驗室晶片的應用提升且簡化實驗操作。
本論文目標是提出毛細力自驅動且易製造的被動式擋板混合器。使用壓克力薄板(2 mm)為基材，並以二氧化碳雷射進行加工後，利用熱壓接合完成晶片，再以光學顯微鏡來進行實驗觀察。
本研究透過觸動閥以及四種檔板結構的搭配，分別為交錯檔板結構、修正型交錯擋板結構、修正型平行檔板結構和蜿蜒流道擋板結構。藉由毛細壓力分析，找出混合器流道高度的設計區間並以實驗驗證之。同時透過2D數值模擬，了解混合器在不同擴散系數下的混合機制與效果。
研究顯示出兩大主要結果：透過對交錯擋板結構的修正，能夠提升混合器流道高度的設計區間(至220~400 μm)。並發現蜿蜒擋板結構具有最長的混合區滯留時間(52秒)與最短的平均擴散距離(300 μm)，因此具有最佳的混合效率(94%)。

Micro-mixer, which is divided into active and passive micro-mixer according to driving method, is an important component in Lab on chip. The passive micro-mixer has advantages of easy fabrication and integration. For more applications and simplifying experimental operation, it is better to use capillary driven without any on or off-chip micro-pump.
In the study, we present a capillary driven and easily fabricated passive planar baffle micro-mixer. The micro-mixers were fabricated in PMMA sheets (2 mm in thickness) by CO2 laser ablation and thermal bonding, and the experimental result were observed and recorded using a CCD camera.
We design four baffle structures with trigger valve. The four baffle structures are staggered baffle structure, modified staggered baffle structure, modified paralled baffle structure, and meander baffle structure. And we investigate the design range of channel height by capillary pressure analysis and take experiment. In addition, 2D numerical simulations were used to estimate mixing mechanism and efficiency in different diffusion coefficient.
Our results show that channel height design ranges (to 220~400 μm) can be promoted by modifying the staggered baffle structure, and then meander baffle structure mixer performs best mixing efficiency (94%) because of longest resident time (52 sec) and shortest average diffusion distance (300 μm) in mixing zone.

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