大面積二氧化碳氣體輔助微熱壓製程開發研究

CO2 Gas-Assisted Micro Hot Embossing Process for Large-Area Replication of Microstructures

朱映達(Ying-Ta Chu)

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(2009年)

https://doi.org/10.6342/NTU.2009.02944

摘要

本研究主要針對大面積壓印技術開發，結合二氧化碳塑化技術、氣體輔助壓印技術進行大面積壓印，提供ㄧ個低溫、快速之大面積微結構複製技術。
本論文提出利用高壓二氧化碳氣體滲入塑化塑膠基板，並利用氣體等向、等壓之施壓特性來進行壓印，可將大面積母模上之微結構於遠低於塑膠基材之玻璃轉移溫度下，完整轉印至塑膠基材上。由於傳統微熱壓製程因使用壓板加壓，壓板之不平行度導致壓力分佈不均，複製面積不大且精度受限；且脆性材料(如矽晶圓、玻璃)不宜做為熱壓模具，受壓時容易發生破裂。此外，壓板(熱盤)加熱冷卻，需將整體熱盤升溫及降溫，不僅製程費時也消耗許多能源。
本製程因利用氣體均勻施壓，並利用二氧化碳能塑化塑膠材、降低製程溫度，成功於低溫在壓克力基板上複製出大面積微結構；即使使用易脆裂之晶圓做為模具，壓印也相當完整。複製出之微結構具經量測證實均勻性與轉寫性良好。
本研究更進一步將製程應用於複製15吋增亮膜V溝結構、微透鏡陣列結構、Fresnel lens、金字塔陣列結構與彩虹全像片等微結構大面積微光學元件，證明本製程之量產應用之可行性。

關鍵字

大面積 ； 二氧化碳 ； 熱壓 ； 增亮膜

並列摘要

In traditional micro hot embossing, substrates are pressed by hot plates, but the pressure distribution is not uniform; Si-wafers and glasses are not proper mold material because of the non-uniform pressure distribution. Furthermore, repeated heating cycle of the conventional hot embossing was not only time wasted but also energy consumed.
This thesis is devoted to the development of an effective fabrication process for the replication of large-area microstructures with uniform pressure at room temperature. This process integrates the plasticizing capacity of carbon dioxide (CO2) and the uniform embossing pressure of gas to perform the large area imprinting. In this study, highly compressed CO2 is employed not only as the plasticing agent to soften the substrate but also the pressing medium. Gas-assisted pressurizing has been proven to provide a uniform pressure distribution over a large-area substrate. As a result, CO2-assisted embossing can be performed under lower temperatures and with lower pressure, and enhances the replication quality by reducing the residual stress in the substrates.
The experimental results show that the microstructures can be successfully replicated onto the whole large area (330 mm × 196 mm) substrate with high replication uniformity. Even using brittle Si-wafer, the shapes and conformations were complete.
The process has been used to replicate microstructure of V grooves for brightness enhancement films (BEF), microlens array, Fresnel lens, pyramid array and rainbow hologram structures onto PMMA substrate. The size is 330mm by 190mm. The potential of mass fabrication of large-area polymer plate/film with microstructures using CO2-assisted process has been demonstrated.

並列關鍵字

large ； carbon dioxide ； hot embossing ； BEF

參考文獻

[41] 邱俊凱， “CO2氣體輔助微熱壓製程開發研究”，臺灣大學碩士論文，民國96年6月

[4] 黃勝田,”雙面微結構超薄件微射出成型之實驗探討”,台灣大學碩士論文,民國93年6月。

[9] 張哲豪,“流體微熱壓製程開發研究”,臺灣大學博士論文,民國93年6月。

[44] 吳炫聰, 李明哲, 林河木, “超臨界抗溶劑法製備次微米級blue 15:6顏料微粒”, 第三屆超臨界流體技術應用與發展研討會, pp.112-119, 2004.

[5] H. Becker, and C. Gartner, “Polymer based micro-reactors,” Reviews in Molecular Biotechnology, Vol. 82, pp. 89-99 (2001).