滾壓式奈米壓印之製程技術整合於大面積軟性電子產品之研究

Developing Nanostructures on Large-Area Soft Electronic Devices by Using Roll-to-Roll Nanoimprinting Technology

劉家興(Chia-Hsing Liu)

指導教授 ： 宋震國

國立清華大學/工學院/動力機械工程學系/博士(2014年)

摘要

本論文提出一個新型的方法論，主要是整合塗佈製程與捲對捲奈米壓印製程，製作近零殘餘層之奈米結構於撓性基板上；其中，塗佈製程為設計塗佈圖案來符合奈米壓印模具結構尺度。論文架構方面，首先是建立一個符合各種塗佈製程於捲對捲奈米壓印的理論模型；接著發展一個方法論，整合塗佈製程與壓印製程的理論模型，並用製程參數的最佳化來達到最小殘餘層厚度的奈米結構。最後，透過實驗結果來驗證理論模型與最佳化方法的正確性。
捲對捲奈米壓印技術是大面積軟性電子產品的關鍵技術之一，在整個滾筒壓印與傳輸的過程中，壓印品質與產量息息相關，包括基板的機械性質，塗膜厚度，傳輸張力與運轉速度等。本研究採用噴墨與凹版印刷的塗佈方式，將低黏度溶液附著於基板上，控制單位面積內光阻的體積，提升塗佈的均勻性。最後，利用蛾眼結構翻製的軟性模具貼附於滾輪上，近零殘餘層結構的光學穿透率在可見光達96.2%，且具有超疏水特性表面接觸角達153°，以及紅外線穿透率降至5%以下。

關鍵字

奈米壓印 ； 近零殘餘層 ； 噴墨 ； 凹版印刷 ； 蛾眼結構 ； 抗反射 ； 超疏水 ； 捲對捲

並列摘要

This thesis proposes a novel methodology that integrates a coating process and roll-to-roll nanoimprint lithography (R2R NIL) to achieve the near-zero thickness of the residual layer of nanostructures. In this study, the coating process is aimed at forming specific patterns, in correspondence with the desired nanostructures, instead of only a thin film on the substrate, for attaining nanostructures with a near-zero residual layer. First, we constructed the theoretical models of various coating processes in association with the R2R NIL. Second, a novel methodology that integrates coating and imprinting processes is proposed based on the developed theoretical models. Third, a method for minimizing the thickness of the residual layer of the nanostructure was developed by optimizing the process parameters. Finally, we performed an experimental study to verify the feasibility of the theoretical models and optimization method.
R2R nanoimprint technology has already shown potential in the manufacturing of soft electronics-related products. However, the filling ratio and web transportation performance of R2R nanoimprinting depends on several mechanical parameters, and their effects must be evaluated for system optimization and device integrity considerations. This study began with the theoretical modelling of coating technologies, such as an inkjet printer and offset gravure coater for coating the ultraviolet resist with the controlled pattern and volume on the polyethylene terephthalate (PET) substrate, to reduce the residual layer. In the imprint process, the original thickness and uniformity of the resist considerably influences the thickness of the residual layer. As the initial thickness of the resist becomes thinner, the thickness of the residual layer becomes thinner accordingly.
Finally, we developed a fabrication process for the large-area antireflection near-zero residual layer nanostructure on a PET substrate with a transmittance ratio of 96.2% in visible spectroscopy, contact angle of 153°, and transmittance ratio of 5% in infrared ray.

並列關鍵字

nanoimprint ； near-zero residual layer ； inkjet printing ； offset gravure coater ； moth-eye nanostructure ； anti-reflection property ； superhydrophobic property ； roll-to-roll (R2R)

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