臺灣博碩士論文加值系統

本研究主要是測定疏水性微流道內壓力驅動液流之滑移現象，實驗模型為以疏水性的PDMS（聚二甲基矽烷）為材料所製作的微流道，微流道的模型寬度為1mm，高度有兩種，分別為50μm、100μm。為消除電動力效應，實驗中以常溫莫耳濃度1M的氯化鈉溶液做為工作流體，以消除液體中可能帶有離子所產生之電動力效應，根據層流理論可推導出具邊界滑移之通道全展流解，建立其流量與壓力梯度及滑移長度之關係。實驗中量測出工作流體流經微流道的壓力梯度跟流量，即可結合理論公式，求出滑移長度。除此之外，本研究也作了接觸角的量測以表徵實驗模型的疏水性。本研究結果顯示較寬大的流道有較長的滑移長度，此點與一般理論認知不同，是實驗的不準確度或是電動力效應所致，有待再深入探討，接觸角量測出PDMS表面接觸高濃度氯化鈉溶液較接觸去離子水更具有親水性。

The objective of this study is to experimentally determine the slip length in the hydrophobic microchannel with pressure-driven liquid flow. Two test model of PDMS material are fabricated using MEMS technique. Both the models are of the same length 5cm and width 1mm, but of different channel height, i.e. 50μm and 100μm. NaCl solution with high molar concentration of 1M is employed as the working fluids for eliminating electrokinetic effect from the ions possibly contained in liquid. According to laminar theory, the solution of fully-developed boundary slip flow can determine the relationship of flowrate with pressure drop and slip length. In the present study, pressure drop and flowrate are measured when working fluid flows in the microchannel. Combining the measurements and the theoretical formula, the slip length can be determined. In addition, contact angles are measured to characterize the hydrophobicity of the models. Different from the existing theories, the present experimental results show that the slip length in the higher channel is larger than that in the lower channel. Measurement uncertainty or electrokinetic effect might be the reason but more profound investigation is worthwhile. The results of contact angle measurement indicate that PDMS surface contacting NaCl solutions with high molar concentration is more hydrophilic than contacting DI water.

誌謝 I
摘要 II
ABSTRACT III
目錄 V
表目錄 VIII
圖目錄 IX
符號說明 XI
第一章 緒論 1
1.1 前言 1
1.2 文獻回顧 2
1.3 研究目標與方法 6
1.4 本論文架構 7
第二章 理論背景 9
第三章 實驗設計與模型製作 11
3.1 流道相關參數 11
3.2 製程儀器與設備 11
3.3 量測實驗儀器與設備 13
3.4 微流道母模製作 15
3.4.1 濕洗淨製程 15
3.4.2 光蝕刻微影製程 15
3.5 微流道製作 17
第四章 實驗方法及流程 32
4.1 實驗方法 32
4.2 初步校正 32
4.3 實驗流程 33
4.4 本實驗環境影響因素 35
第五章 數據擷取與不準確度分析 38
5.1 數據擷取 38
5.2 數據分析 38
5.3 不準確度分析 38
第六章 結果與討論 43
6.1 滑移長度之決定 43
6.2 接觸角之量測 44
第七章 結論與未來展望 55
7.1 結論 55
7.2 未來展望 56
參考文獻 57
附錄一、雙面光罩對準曝光儀操作程序 59
附錄二、接觸角量測 62

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