本研究利用接觸式金屬轉印技術 (Contact transfer and metal mask embedded lithography) 與乾式蝕刻，在透光性材料表面製作次微米等級的微結構，以改善其光學特性；另外，在理論與模擬方面，根據有限元素法 (Finite element method) 分析此一次微米結構的光學特性，已達到最佳設計的目的。主要應用對象為具抗反射功能的光學元件。
　　在實驗部分，根據接觸式金屬轉印技術完成蝕刻遮罩，再控制乾式蝕刻製程的氣體流量、射頻功率、製程壓力、與蝕刻時間，成功地在光學玻璃上定義出線寬200 nm、週期400 nm、高度135 nm六角最密排列之柱狀結構，並利用分光光譜儀量測出此單面抗反射結構的光學玻璃之穿透率，其穿透率相較於平板光學玻璃提升約2%。進一步更利用軟性壓印模仁可撓曲的優點，在具有曲率的光學凸透鏡上，蝕刻出次微米等級的柱狀結構；在不影響其光學聚焦與成像的能力下，增加其光學穿透特性與抗眩光的效果。本技術未來的應用甚廣，例如抗反射玻璃、提升顯示器顯示品質、增加太陽能電池光吸收率、解決眩光問題、或是提升光學系統的穿透率...等等。

　　In this study, contact transfer and metal mask embedded lithography (CMEL) and plasma etching process are applied to define and pattern arrayed sub-micrometer structures on the surface of transparent material. These structures can be used to improve optical properties and performance. By using a commercial finite element method (FEM) software for simulation, optimization on the design of surface structures is accomplished. The main application of this study is to improve the optical properties of anti-reflective optical devices. In experiments, an etching mask is first defined by CMEL technology, and followed by a dry etching process with controlled gas flow, RF power, chamber pressure, and etching time. Arrayed pillar-like structures are successfully patterned on fused quartz and glass materials with a hexagonal arrayed period of 400 nm, a diameter of 200 nm, and a height of 135 nm.
　　The transmittance of the patterned substrates has been measured by a spectrophotometer. It is found that the transmittance of the glass with single sided antireflective structures is increased by approximately 2 %. Furthermore, using the advantage of a flexible mold, sub-micrometer structures can also be made on the curved surface of an optical lens. These structures can increase the optical transmission and obtain anti-glare effect of the lens while in the mean time having no affect on its imaging ability. The application of this study is extensive, such as anti-reflective glass, anti-glare film, improvement of display quality, absorption enhancement of solar cell, and improving transmittance of optical system.

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