本研究欲發展一種新式奈米壓印系統與壓印方法，利用紫外光固化之奈米壓印製程技術搭配具厚度變化之可撓式模具，可應用於圖案化藍寶石基板 (Pattern Sapphire Substrate, PSS) 的量產製程。其基本架構為：使用具厚度變化之撓性壓印膜仁(Flexible mold)、紫外光固化之阻劑膠(UV-curable resist resin)、四吋基板、與圓形軸對稱擴散式壓力流動(radial squeezing flow)的壓印方法；實驗中根據可撓式模具的柔軟特性，能完整貼覆於翹曲的基板上，改善傳統硬質壓印模具之高成本及低良率的問題，提升奈米壓印技術在產業應用上的可行性與廣泛性；另外，紫外光固化之壓印製程有著製程快速及常溫操作的優點，因此可應用於量產的製程。另外，在理論及模擬計算方面，根據有限元素法(Finite element method)分析不同厚度形貌之可撓性模具的變形，及不同時間點下之壓印過程中可撓式模具與基板間的壓力分佈及變形；藉由壓力感測系統(Pressure sensing system)量測實驗中真實壓力分佈，比對模擬及真實數據，修正模擬的真實性，由模擬算得壓印過程中各階段的壓力分佈，或進階模擬阻膠劑的流動情形與最佳施力值，找出更適當的壓力作動。
本文成功在四吋玻璃上製作出無殘留層的柱狀光阻結構，其柱狀結構製程是以傳統的矽基硬質模仁作為母模，翻製出高透光性的PDMS模具，將此模具無結構的背面黏合不同厚度之曲面PDMS，完成一具厚度變化且具結構之PDMS模具，並以此模具執行壓印製程；於基板中心滴上60 μL阻膠劑，基板與受壓變形之PDMS將阻劑膠由中心向外流動，再由紫外光固化膠後，可壓出無殘留層、線寬2 μm、週期3 μm、高度2 μm之柱狀光阻結構，改善傳統奈米壓印的殘留層問題，且以滴定阻膠劑取代旋轉塗佈，省去一製程步驟外，大量減少在旋轉塗佈機將阻劑膠旋塗至基板外的不當浪費。

This thesis proposes a new type of ultraviolet (UV) nanoimprinting lithography based on soft polydimethylsiloxane (PDMS) molds with varying mold thickness. Due to the deformable and flexible characteristics of the soft mold, it is possible to achieve a conformable contact with substrates as well as a controllable contact pressure distribution during imprinting. Finite element method is adopted to analyze the mold deformation and mold/substrate contact pressure for different geometrical designs of the mold and mechanical loading steps. Experimentally the contact pressure is measured by an area pressure sensing system and compared with simulation results.

To apply this imprinting method for manufacturing of patterned sapphire substrates (PSSs), PDMS molds with varying thickness are prepared through molding processes on a silicon mold containing hexagonally arrayed micro-pillars. A drop of UV-curing resin (60 μL) is placed in between the initially deformed PDMS mold and a sapphire substrate. Hexagonally arrayed pillar-shaped PR microstructures are formed by mechanical loading forces and UV radiation. The diameter and center-to-center pitch of these pillar arrays are 2 μm and 3 μm, respectively. The imprinted height is 2 μm without any residual layer thickness.

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