本研究為能解決微型毛細泵吸環路(Micro Capillary Pumped Loop, MCPL)運作時，蒸汽線傳輸壓阻過大的問題，採用微機電製程技術製作一定熱通量熱泡式微泵浦來探討微管道內移動汽泡之物理機制。實驗透過管道內部表面改質技術製作親疏水性相間區域，利用表面能量分佈的特性，在不加外力驅動下而能產生快速移動汽泡的驅動力。
在晶片製作過程中，因鋁化鉭(TaAl)合金無法承受熱融合接合時的高溫(約630℃)，然研究發現採用聚二甲基矽氧烷(PDMS)為中間層時，可成功於低溫(約180℃)條件接合並製作出所需晶片。研究中對於汽泡成核(nucleation)、成長(growth)、與移動(movement)等現象的探討乃採視流觀察法；此外，研究亦比較相同熱通量但不同加熱位置及相同加熱位置但不同熱通量的條件下，觀察管道大小對汽泡的影響。實驗結果顯示管道寬為500micron時，在微加熱器h2位置因管道開始發生幾何變化而為觀測汽泡移動之最佳位置。當h2以10V(93mW)電壓輸入，汽泡成長到約1000micron時，僅發生左右震盪現象，此時系統應達熱平衡。但當管道寬縮為100micron後，輸入6.2V(76mW)電壓於h2時，則可觀察到汽泡不斷往前移動的情形，顯示管道尺寸效應對系統熱泡的移動存在明顯影響，當管道尺寸縮小時，產生穩定汽泡所需熱通量亦越低，晶片系統也越易產生熱傳效果。

The focus of this study is to solve the problem of high pressure drop when fluid passes through the vapor line in micro capillary pumped loop, MCPL. In this study, MEMS technology is used to fabricate thermal bubble pump that has constant heat flux to investigate the mechanism of driving bubbles. By surface modification, the micro channel has hydrophilic and hydrophobic regions. The distribution of surface free energy will make bubbles move without external force.
Because the TaAl alloy can’t stand the high temperature (630℃) of thermal fusion bonding, this study carries out a low temperature (180℃) bonding method. The device fabricates successfully by using PDMS as the intermediate layer between two substrates. In the experiment, observation of flow visualization is used to investigate the bubble phenomenon including nucleation, growth, and movement. Effects of different heater position with the same heat flux and different heat fluxes in the same position were compared. Furthermore, the effect of channel width is discussed. The result reveals that when channel width is 500micron, heater in the geometry change of channel (h2) is the best position to observe bubbles move or not. When 10V (93mW) is applied to h2, bubble will grow to 1000micron length and reach thermal equilibrium. However, at this state the bubble only oscillates. When channel width reduce to 100micron and 6.2V (76mW) is applied to the heater, the bubble will move forward continuously and have the effect of heat transfer.

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