捲對捲微接觸印刷之溶劑預潤濕製程研發

Solvent Pre-wet of R2R Micro-contact Printing

郭憲哲(Hsien Che Kuo)

指導教授 ： 鄭榮偉

國立中正大學/工學院/機械工程學系/碩士(2014年)

摘要

本實驗室致力於軟性電子製程開發，其重點在於有機薄膜的圖案化技術，而本技術的關鍵點在於如何能夠在大氣下，達到均勻的有機薄膜圖案。而本實驗室開發「結合使用溶劑預潤濕之微接觸印刷技術」，溶劑潤濕的優點在於可以使本實驗室使用的印模聚二甲基矽氧烷(poly(dimethyl siloxane)，PDMS)塗佈高分子材料時，增加薄膜表面的平整性。目前此技術已被證明預潤濕對於微接觸印刷技術是有利的，但預潤濕到何時已足夠該停止，以往皆是由經驗決定並無統一的標準，本文將對於溶劑預潤濕製程訂定一套標準。
在本論文中以接觸角量測儀，進行接觸角之量測，從接觸角角度變異量，探討預潤濕是否足夠或過多。在使用P3HT in toluene溶液塗佈中，利用測試液二碘甲烷先滴至PDMS矽膠上量測接觸角。實驗結果，顯示了接觸角標準差在0.5度下塗佈結果最佳。但因先前皆是以手動方式完成預潤濕之動作，再放置接觸角量測儀上，測量其角度變化，在本論文中我們將視訊攝影機架設於本實驗室開發之工業級捲對捲微接觸印刷原型設備機台上，以視訊鏡頭拍攝液滴，再經過影像後處裡，求得接觸角，再討論預潤濕是否足夠。
最後結合溶劑預潤濕結果，在捲對捲微接觸印刷原型設備機台上印製寬5.5 cm，長為1 m與寬20 cm，長1 m 之P3HT無圖案化之薄膜，並討論塗佈結果與塗佈用之刮刀轉動與否、PDMS矽膠厚度均勻性、滾輪平行度以及實驗環境之關係，提出未來機台改進方法，以達到捲對捲微接觸印刷高品質之圖案化薄膜的最終目標。

關鍵字

接觸角 ； 溶劑預潤濕 ； 微接觸印刷 ； 捲對捲

並列摘要

Our group has devoted to flexible electronics fabrication for a long time and been focused on fabricating patterned organic thin films. One major research issue is how to make a uniform organic thin film with patterns in atmospheric environment. And our group develops a innovative micro-contact printing (μCP) process with solvent pre-wetting technique. It can improve the uniformity of printed thin films when we use the poly(dimethyl siloxane) (PDMS) as the printing stamp.
The solvent pre-wetting has been proved useful in μCP, but nowadays we don't have a reliable criterion to determine if the pre-wetting is enough or not. In this thesis, an effective criterion for solvent pre-wetting has developed. Specifically, variations in the contact angles on the pre-wetted PDMS stamp is proposed for the pre-wetting criterion. The experiment result shows the best coating result is when the standard deviation of contact angles is lower than 0.5 degree. To implement the pre-wetting criterion on a roll-to-roll (R2R) machine, we use a web camera to take pictures of the pre-wetted PDMS along with the droplet of a testing liquid, and then use image processing algorithms to calculate the contact angles for pre-wetting evaluation.
At last we combine the solvent pre-wetting and self-adjusting blade coating, another previous technique developed in our group, to print large-area thin films without patterns by using a prototype R2R μCP machine. We successfully print large-area poly(3-hexyl thiophene) (P3HT) thin films with dimensions of 5.5 cm x 100 cm and 20 cm x 100 cm, respectively. Finally, possible improvements to the prototype R2R μCP machine regarding self-adjusting blade coating, thickness uniformity of PDMS ring stamps, parallelism among rollers and environmental controls were identified for future high quality R2R μCP printing.

並列關鍵字

Micro-Contact Printing ； Solvent Pre-wet ； Roll To Roll ； Contact Angle

參考文獻

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