表面電漿子元件的設計與製造及其在光學微影上的應用

Design and fabrication of plasmonics device and its application to photolithography

張晉愷(Chin-Kai Chang)

指導教授 ： 葉超雄 ； 李世光

國立臺灣大學/工學院/應用力學研究所/博士(2009年)

https://doi.org/10.6342/NTU.2009.03118

摘要

由於繞射極限的限制，使得半導體製程上的可製作的線寬大小受到了限制。除了降低入射光波長外或是利用浸潤式微影外，也可以提高透鏡的數值孔徑來縮小線寬。但上述許多方法的製造成本過於昂貴，所以使得近年來半導體製造的發展受到了限制。
近年來奈米光學的理論與製作已經逐漸發展成熟，本論文使用表面電漿光學的原理來設計光學元件。我們提出了數種金屬奈米結構，包含雙面金屬奈米結構(Double sided metallic nanostructure)，多圓環奈米金屬結構(Multi-ring metallic nanostructure)，圓環溝槽金屬奈米結構(Ring containing circular groove metallic nanostructure)，並且利用聚焦離子束在金屬基板製作出上述之金屬奈米結構，在實驗方面，我們使用共焦顯微光譜儀量測金屬奈米結構的對於光學上的特性。其中我們也發現具有銀金屬基板的金屬奈米圓環結構中，對於特定的入射光波長，其出射光具有高穿透能量、次波長聚光點、及長焦深等特性。這些獨特的光學特性可使得電漿子透鏡應用在光學微影上。
在應用方面上，本論文將多圓環金屬奈米結構同時整合在現有的雷射直寫儀(Laser writer)以及微透鏡(Micro lens)上。在雷射直寫儀中，當我們將多圓環金屬奈米結構整合至系統上時，該系統具有可以在大氣環境中，直接在光阻上可寫出具有次微米的大小的圖案。而當整合在微透鏡上時，我們可以使得出射光的聚焦點更小，能量更強。論文中也利用單圓環奈米金屬結構的特殊光學特性，在負光阻上直接製作出高深寬比的次波長結構，以證明我們所設計之金屬圓環結構，具有可以製作高深寬比結構的能力。

關鍵字

奈米光學 ； 表面電漿 ； 次波長結構 ； 光學微影

並列摘要

Due to the limitation of optical diffraction, it constrained the ability of fabricating line width in semiconductor process. In addition to reduce the wavelength and immersion lithography, we also could increase the lens of numerical aperture to enhance the optical resolution. However, they are very expensive for above mentioning methods, and the development of semiconductor was constrained recently.
Recently, the theory and experiment of nano-optics has developed well. This thesis uses the principle of surface plasmon to design and fabricate the plasmonics device. We propose the some metallic nanostructure included double sided metallic nanostructure, multi-ring metallic nanostructure and ring containing circular groove metallic nanostructure, and use the focused ion beam to fabricate these nanostructures. In optical experiment, we use the confocal microscopy to measure the characteristics of nanostructure. We found the structure on the silver film have unique optical properties, which have high optical transmission, long depth of focus and subwavelength focal spot for specific incident wavelength. These properties could make the plasmonics lens to become a tool of optical lithography.
In application, we use the multi-ring metallic nanostructure to integrate on the laser writer and microlens. With integrating on the laser writer, we could use this system to make a sub-micron pattern in the atmosphere. Besides, we could obtain a novel focusing lens as integrating with microlens. Finally, we use the single metallic ring structure to fabricate the high aspect ratio structure at negative photoresist directly. It could prove our metallic lens to possess good optical properties.

並列關鍵字

Nano Optics ； Surface Plasmon ； Subwavelength Structure ； Optical Lithography

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