創新型微奈米軟模轉印技術之研發與應用

Development of a Novel Micro/Nano-stamping Technology with Applications

張致遠(Chih-Yuan Chang)

指導教授 ： 楊申語

共同指導教授 ： 黃榮山 ； 謝國煌

國立臺灣大學/工學院/機械工程學研究所/博士(2006年)

https://doi.org/10.6342/NTU.2006.00480

摘要

微系統元件是應用於數位光電、通訊、顯示器、生物醫療與檢測儀器的關鍵零組件，傳統的微射出與微熱壓複製量產技術，需要複雜製程、剛性模具與昂貴設備，及高溫、高壓、冷卻的過程，耗時且昂貴。
本論文致力於研發低溫、低壓及快速成型的微奈米軟模轉印技術。首先整合微機電製程與矽膠(PDMS)鑄造技術，製作具微結構圖案之彈性軟模，接著調製紫外光固化高分子材料，並使用自行研發的微轉印成型設備，進行微奈米結構元件的轉印與製造。
本論文之主要研究內容包括：微透鏡陣列之軟模壓印成型、微透鏡陣列之軟模沾印成型與黑色薄膜元件之軟模轉印成型。
在『微透鏡陣列之軟模壓印成型』方面，利用具有微圓孔陣列圖案的PDMS軟模與塗有透明UV固化光阻的塑膠基板，進行接觸壓印。由於毛細作用與表面張力，光阻受壓於模具的圓孔內形成透鏡狀，最後以紫外光固化材料後，就可在塑膠基板上得到微透鏡陣列結構；此製程並可利用壓印時間的調節來控制微透鏡的高度與形狀。
在『微透鏡陣列之軟模沾印成型』方面，首先將UV固化材料塗佈於具有微圓孔陣列圖案的軟模表面，並使材料填入模具表面的圓孔模穴內，刮除軟模表面殘餘的材料後，進行軟烤，再將軟模與透明基板置入微轉印機台中進行沾印。在沾印過程後，軟模表面之圓孔內的材料因濕潤現象與表面張力效應，而在基板上形成透鏡狀結構，最後利用紫外光將材料固化，而得到微透鏡陣列元件。此製程並可利用不同基板濕潤特性來控制微透鏡的幾何形狀、曲率、焦距等光學特性。
在『黑色薄膜元件之軟模轉印成型』方面，利用奈米等級的碳黑微粒與UV固化樹脂，調製出黑色樹脂，並配合具有微細線條陣列圖案的PDMS軟模具，在基板上轉印出黑色線條薄膜，並且藉由改變黑色樹脂中溶劑的含量，控制轉印成品的薄膜厚度，進而製作出不同膜厚的黑色薄膜元件，可符合TFT-LCD彩色濾光片產業的需求。
本研究成功建立微機電製程、矽膠(PDMS)鑄造、微奈米軟模轉印複製與紫外光固化成型之整合技術平台。在製造原理上，此法兼具創新性與突破性；在製造特性方面則具有低溫、低壓、低成本與可快速量產(整個製程成型時間約10∼20秒)的優勢。此技術平台具有製程簡易、快速、低成本與可量產等優勢，未來可應用於微系統元件之製造上，可提升微結構產業。

關鍵字

軟模 ； 微奈米轉印 ； 微透鏡陣列

並列摘要

In recent years, micro-parts and micro-systems has been widely used in various applications such as information processing, optical communication, optoelectronics, flat panel display and bio-technology. With cost of paramount concern for many new micro-system applications, polymers are becoming one of the most practical materials for mass production. Micro-injection molding and micro-hot embossing are regarded as the two best mass-production methods to replicate microstructures and micro-parts. However, the processes involve high temperature, high pressure and require electroformed metal mold and expensive facilities. They are complicated, time-consuming batch-wise processes.
From this perspective, an innovative micro- and nano-stamping technology for rapid fabricating microstructure and micro-optical devices has been proposed and developed. This low pressure/low temperature stamping process reduces cycle time and allows continuous processing. The proposed technique uses a soft PDMS mold instead of the electroformed metal mold. To further improve the productivity, the process uses UV-curable photopolymer and employees UV light to cure the photo-polymer.
In this study, a micro and nano-stamping facility with UV exposure capacity has been designed, constructed and tested. The innovative low temperature/low pressure process has been used to fabricate polymer microlens arrays and black matrix devices. The cycle times are less than 20 seconds. The microlens arrays and black matrix devices have smooth surface and uniform property. The shape and height of micolens can be controlled with a proper combination of pressing pressure, pressing duration and UV curing dose. The thickness of black matrix can be adjusted by changing the concentration of black resin.
In summary, this low cost and high efficient method has many advantages over the conventional techniques. It is believed that the novel process is expected to give an impact to the micro-system fabrication technology and to create a highly value-added technology in optoelectronics industry.

並列關鍵字

soft mold ； micro-/nano-stamping ； microlens array

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