低殘留層加溫轉印製程開發與應用

Development of Thermal Imprinting Process for Low Residual Layer and Applications

翁詩緯(Shih-Wei Weng)

指導教授 ： 楊申語

國立臺灣大學/工學院/機械工程學研究所/碩士(2015年)

https://doi.org/10.6342/NTU.2015.01291

摘要

微奈米壓印技術在結構複製上具備高解析、高產能、低成本且可製作大面積等優勢，然而微奈米壓印技術在壓印膠體成型結構後，容易在結構與結構之間留下殘留層，必須以反應離子蝕刻、電子束蝕刻等技術去除，耗費時間與金錢成本。
本研究針對過去低殘留層轉印技術總是著眼於模具或結構製作本身改善，無法廣泛應用於不同結構的缺點，改以製程方式角度切入，開發同時加壓與加溫的加熱型濕式轉印技術，用於一次性轉印出不同的低殘留層結構。研究主要分成三個部分：首先為低殘留層壓印製程的設計與開發；二為低殘留層壓印製程在陣列式排列金字塔型結構上的成型測試；三為在微小尺寸的圓錐與圓柱結構的測試。
第一部分選用V型溝槽結構來開發製程，探討溫度與壓力對壓印的影響，並建立同時加壓與加溫的製程，稱為加熱型濕式轉印，讓結構尖端尚未固化的膠體擠入模穴，得到低殘留層的轉印結果，並以雷射共軛焦顯微鏡進行量測，討論其成型結果與膠體旋轉塗佈厚度之關係，確立製程，並且找出壓力與旋轉塗佈厚度對殘留層厚度的影響；第二部分將低殘留層製程應用於陣列式金字塔型結構的成型，先以黃光微影製程製作母模，並翻製成PDMS模具，進行加熱型濕式轉印壓印參數的探討，確認低殘留層製程可應用在其他陣列式結構上；第三部分將低殘留層壓印製程應用於圖案化藍寶石基板(Pattern sapphire substrates, PSS)的圓錐與圓柱結構的成型，並分析比較在緊密排列pitch約3 um的結構壓印壓力與殘留層厚度的關係，結果顯示在40 kgf/cm2時甚至可使殘留層厚度低於200 nm，符合PSS製備的需求。

關鍵字

微奈米壓印 ； 殘留層 ； 圖案化藍寶石基板

並列摘要

In recent years, imprinting of large-area micro and nanostructures have been widely used in many products, such as monitor, solar panel and bio-sensor etc. However, the removal of the residual layer after the imprinting is complicated and time-consuming. Most are processed using a reactive ion etching (RIE) or electron-beam (E-beam) lithography post processing step. Therefore, to imprint micro and nanostructures without the residual layer in a simple and inexpensive way is a big challenge.
This research is devoted to developing an imprinting process which can reduce the residual layer. There are three main topics in this research: the development of the low residual layer imprinting, test of the imprinting process on the pyramid structures, and the application of this process on the imprinting of array of column and cone-shaped structures with low residual layer.
First of all, we chose a simple microstructure (v-cut) and a proper resin for the development of this process. After investigating the relationship between the resin, temperature and pressure, we developed the heating wet transfer process, the pressure squeezed the resin from the convex surface into the concave of the mold, and the heat solidified the whole resin in the cavity. Then, we investigated the effects of spin-coating and the pressure on reducing the residual layer. With above parameters, the process of low residual layer imprinting v-cut microstructures has been developed.
Second, we applied the process on the pyramid structures to prove that the process could be widely use on different mold. The pyramid structures mold was fabricated by lithography method. We successfully formed the pyramids with low residual layer with our process and compared the parameters on different mold imprinting.
Lastly, the pattern sapphire substrates (PSS) has been chosen as the master mold on our process as the application. After discussion of the relationship between the imprinting pressure and the residual layer thickness, we successfully imprinted the structure with the residual lower than 200 nm with the process.

並列關鍵字

microimprinting ； the residual layer ； pattern sapphire substrate

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