製作奈米模板並探討嵌段共聚物於奈米模板下之自組裝現象

Fabrication of Nano-Templates for Local Self-Organization of Block Copolymers

巫清景(Wu, Ching Jing)

指導教授 ： 李明昌

國立清華大學/電機資訊學院/光電工程研究所/碩士(2015年)

摘要

高分子嵌段共聚物(Block Copolymers)具有自組裝(Self-Assembly)的特性，可藉由控制聚合物鏈段之長短與成模條件來改變不同的自組裝型態。在過去的二十年，嵌段共聚物(Block Copolymers)的自組裝特性可經由裂解而得到奈米結構圖案的研究備受矚目，然而為了能使嵌段共聚物薄膜有實際用途，因此控制嵌段共聚物的自組裝結構是必要的。
本論文利用直接誘導嵌段共聚物自組裝的方式(Directed Self-Assembly, DSA)，即為使用特定曝光方法搭配垂直整合法製作出具有結構化的奈米模板來誘導嵌段共聚物的自組裝排列，來了解奈米模板與嵌段共聚物的交互作用下的表現。
本研究保有光學微影法的優點，配合半導體製程製作出多元之垂直整合結構。提供由上到下的奈米模板製造技術(Top-Down)，使具有大面積、底部平坦、銳角以及高陡峭壁之特性，之後將嵌段共聚高分子填入其中，觀察由下到上自組裝現象的製造技術(Bottom-up)。
本研究使用的高分子量嵌段共聚物為PS-PLLA poly(styrene-(L-lactide))，觀察於奈米模板中分子之自組裝特性，利用溶劑回火系統產生微相分離來製造出具有規則性之奈米型態。藉由以上方法以期能製作出大面積且有序的奈米圖騰，並了解奈米模板與嵌段共聚物間的交互作用。

關鍵字

奈米模板 ； 晶向 ； 大面積 ； 多重微影 ； 嵌段共聚物 ； 自組裝 ； 聚苯乙烯-聚乳酸 ； 微相分離

並列摘要

The macromolecules synthesized by block copolymers can be controlled in size and shape, by choosing the length of the polymer chain segments to change the self-assembled patterns. In the past two decades, the fabrication of nanostructured thin films from the self-assembly of degradable block copolymers (BCPs) has attracted extensive attention. To create useful BCP thin films for practical uses, controlled ordering of self-assembled nanostructures is essential.
In this research, we used a top-down approach --- a unique lithography and vertical integration method to make nano-templates for studying the BCP self-assembly in the templates. We keep the advantages of optical lithography to fabricate various nano-templates in a large area. The structures of nano-templates have flat bottom surface, acute corner and highly steep sidewall. Then we fill the block copolymers into the nano-templates to observe the phenomenon of self-assembly in nano-templates.
This thesis studies the macromolecule synthesized by two block copolymer systems --- PS-PLLA poly (styrene-(L-lactide)) self-assembled on the nano-templets, and uses the solvent-annealing approach to create the regular nano-patterns via microphase separation. Through this method (DSA), we demonstrate orderly self-assembled nanoporous structures in those patterned nano-templates.

並列關鍵字

nano-templates ； Orientation ； Large-Area ； Multiple Lithography ； Block Copolymers ； Self-Assembly ； PS-PLLA ； Microphase Separation

參考文獻

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