微影製程用光阻劑研究

A study of photoresists for microlithography

林振宏(Chen Hung Lin)

指導教授 ： 王紀

元智大學/工程學院/化學工程與材料科學學系/碩士(1998年)

摘要

摘要
本研究主要合成不具苯環的193 nm DUV的光阻劑，在樹脂的部份，採用不同單體組成之acrylic系列的三元共聚物poly(MMA-TBMA-MAA)，並分別合成各單體的均聚合體，藉以分析光阻劑的性質。光酸部份則使用TPS-As。目的為探討適用於微影製程的最佳組成，及討論新型193 nm型光阻的劃時代性光阻材料。此光阻系統中控制溶解度的去保護基團TBMA(甲基丙烯酸第三丁酯)最佳含量為25~35 mol%，而提供顯影能力及附著力的MAA(甲基丙烯酸)則，最適含量約為20 mol%，其餘則搭配適當含量的MMA(甲基丙烯酸甲酯)。
材料分析方面，以FT-IR鑑定成分，並藉IR光譜討論聚合反應中所產生的氫鍵效應。使用NMR及先前研究所得EA的結果鑑定共聚物的組成。以GPC來量測各聚合物的分子量。以熱分析實驗(DSC及TGA)測得各聚合物的玻璃轉移溫度及熱穩定等相關溫度，並探討氫鍵效應對共聚物玻璃轉移溫度的影響。
在微影成像上，採用旋轉塗佈的方式成膜，以準分子雷射曝光、後烘烤、顯影，微影結果以SEM觀察，討論不同組成的共聚物能成像的微影條件。

關鍵字

光阻 ； 光酸 ； 去保護反應 ； 微影

並列摘要

ABSTRACT
We analyzed chemically amplified photoresist(CAMP) designed for 193 nm microlithography. The CAMP is composed of a photoacid generator(TPS-As), and a terpolymer(poly(MMA-TBMA-MAA)). Both of them were synthesized in this laboratory.
The content of the protection group in the photoresist(PR) was determined to be 25~35 mol%. It is attributed to the fact that less protection group results in a lack of dissolution when developers are used and more protection group exhibits a formation of insoluble surface layer. It was necessary from adhesion requirements to contain 20 mol% of MAA in this PR and the rest was MMA.
Hydrogen bonding effect in PR was evidenced by the shifts in the
FT-IR and this resulted in a higher glass transition temperature(Tg). From NMR results, the composition of PR was calculated. GPC was used for the determination of molecular weight distribution of PR. DSC was used to revel the Tg of PR. TGA was used to determine the temperature for deprotection reaction of PR to take place.
Moreover, the resist patterns were investigated using SEM. The composition of the MMA-TBMA-MAA copolymers and a photoacid generator content have significant effects on the process of microlithography.

並列關鍵字

photoresist ； photoacid ； deprotedtion reaction ； lithography

參考文獻

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