液滴揮發的現象及其溶液沉積導致形成微/奈米結構的成型機制已廣泛地被探討多時，然而大多數的研究多著重在液滴於基材表面上開放空間的揮發情形，本研究主要探討蛋白質溶液在微流道結構內部的揮發現象，操作參數包括模具設計、微流道幾何尺度、溶液濃度、基板特性和粒子種類等，以探討一維微/奈米線性結構成型的影響。
實驗結果發現蛋白質多以連續性的線狀結構沉積在微流道的的壁角，線高介於微/奈米尺度之間，線長結構可達一公分。相較於兩端開放或兩端封閉的設計，一端封閉/一端開放的模具設計能夠提升微/奈米線狀陣列的整體均一性；當微流道寬度相同(50μm)，深度較低(2μm)的流道易使溶液均勻填滿流道內部。使用表面親水的基板(玻璃，矽晶圓)易將蛋白質溶液填入微流道，且得到較佳的微/奈米線狀結構；若使用較疏水的基板(PMMA，PET)，不僅無法均勻填滿流道內部，在揮發沉積的過程中也無法形成比親水基板較佳的微/奈米線狀結構。經由螢光強度的追蹤，我們得知微流道兩端或兩側與大氣連通的距離越短，則會提高蛋白質溶液揮發沉積的速率。若欲製備無機的線狀結構，如SiO2，則可於SiO2溶液中加入BSA蛋白質，藉由BSA溶液的揮發流動沉積，在高溫鍛燒後，得到無機氧化物的一維微/奈米結構。

Although droplet evaporation and that leading to formation of micro/nanostructures have been widely studied for a relatively long time, almost all the studies involve the droplet dispensed on a flat substrate. In this study, we investigate evaporation of protein solution inside the microchannels, the so-called confined space. The effect of various processing parameters such as design and dimensions of the microchannel array, solution concentration, solutes, and properties of the substrate on the deposited structures are discussed. It is found that protein molecules can deposit at the corners of the microchannel to form continuous line structures with height at sub-micron or nanometer scale and length up to 1 cm. The microchannels with one end open to the atmosphere provide better uniformity of the line structures on the entire substrate. When using the hydrophilic substrates, the protein solution can be easily filled in the microchannels and better line structures can be obtained. The evaporation rate increases substantially when the microchannels are near the edge of the stamp. Besides the protein line structures, inorganic line structures such as oxide can be generated by filling the microchannels with the solution having oxide particles along with protein molecules, followed by evaporation/deposition and sintering process.

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