氣體輔助PDMS模具壓印製程開發研究

Development of Gas-Assisted PDMS Mold Imprinting Process

鄭芳松(Fang-Sung Cheng)

指導教授 ： 楊申語

國立臺灣大學/工學院/機械工程學研究所/博士(2007年)

https://doi.org/10.6342/NTU.2007.01686

摘要

傳統微奈米壓印方法藉由壓板機構來對基材進行加熱及加壓成形，容易導致壓力施加不均勻、壓印面積受限制以及微結構複製精度不良等問題；而且脆性材料（如矽晶圓、玻璃）基材及模具受壓時容易發生破裂，以及非平面（如曲面）基材不易複製微結構等缺陷。由相關文獻可知，PDMS材料可有效縮短微結構複製週期並作為模具使用，同時可克服非平面基材在均勻壓力及接觸之壓印問題；此外氣體具有均勻且等向之特性，在大面積及非平面基材上施壓具有良好的效用，因此兩者合併應用的研究就顯得更為重要。
有鑑於此，本論文首先針對大面積尺寸基材壓印技術做研究，著重於氣體輔助大面積熱壓印實驗機台的架設、12吋PDMS模具的翻製以及12吋晶圓壓印之複製成形的探討；再來針對PDMS模具紫外光壓印技術的開發、PDMS模具壓印變形探討以及曲面基材的壓印在光學元件應用上進行研究。研究分為三部分：第一是針對PDMS模具壓印變形做研究，著重於液靜壓機構輔助紫外光壓印實驗機台的架設及PDMS模具壓印過程微結構變形的實驗探討；第二是利用ANSYS有限元素分析軟體模擬液靜壓機構在不同壓印製程參數對PDMS模具壓印變形的影響，並與實驗結果作比較；第三是針對凹曲面基材壓印技術做研究，著重於PDMS軟模之可撓性的應用以及微光柵結構於凹曲面之複製以及分光效果的探討與模擬。
實驗結果顯示：(1)以氣體輔助PDMS模具進行大面積熱壓印製程可在12吋晶圓上完整複製出微結構圖案；(2)以氣囊式輔助壓印技術配合PDMS模具可達到液靜壓機構，有效控制PDMS模具在壓印過程中的變形現象；(3)成功建立ANSYS數值結構模型以模擬PDMS模具在不同製程參數之變形狀態，且分析結果與實驗量測結果接近；(4)成功在凹曲面上完整均勻的將微結構複製，且將具300nm微光柵結構壓印複製於Rowland circle上，充分以製程簡單、成本低及良好複製微結構以得到預期分光之效果，有效提升於光學元件之製程開發及其應用上。

關鍵字

氣體輔助壓印製程 ； 液靜壓機構 ； PDMS模具 ； 曲面壓印 ； 大面積壓印

並列摘要

For conventional hot embossing, the substrate and the stamp are brought into contact and are compressed directly by the hot platen. The accuracy and area of replication are limited due to the inherent non-uniform pressure distribution. Si-wafers are too brittle to be used as embossing the molds with the conventional hot embossing operation. To enhance close contacting and uniform pressuring during large area and curved surface imprinting, PDMS mold and gas pressure are employed in this study.
This thesis probed into the research with regard to large area substrate imprinting, emphasized how to construct experiment machine applied on the gas-assisted hot imprinting and renovate 12 inch PDMS mold and explored the replication of 12 inch wafer imprinting. The next process is devoted to the development of PDMS mold UV-imprinting, the deformation of PDMS mold and curved substrate imprinting applied on optics components. The gasbag assisted imprinting system is developed and tested.
The results confirmed that replication patterns on 12-inch silicon wafer and 2-inch curved substrate in one imprint step using PDMS mold and gas pressure mechanism is demonstrated. With the hydrostatic pressure mechanism, the deformation of the PDMS mold is controlled. This study demonstrates that pattern replication on large/curved surface with low cost and simple process is feasible.

並列關鍵字

gas-assisted imprinting process ； hydrostatic pressure mechanism ； PDMS mold ； curved imprinting ； large area imprinting

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