表面電漿子透鏡之設計與製備及應用於直寫微影

The Design and Fabrication of Surface Plasmonic Lens and Its Application for Direct-Write Lithography

劉俊宏(Jiun-Hung Liu)

指導教授 ： 李有璋

中原大學/工學院/機械工程研究所/碩士(2019年)

https://doi.org/10.6840/cycu201900713

摘要

半導體產業中的微影製程是用以定義微小元件上的電路圖案，而其製程技術的發展直接影響了科技產業的進步，原因在於相同大小的電子產品中，電晶體數目的增加會使其效能相對的提升，因此對於微小化技術的發展一直都是各界努力的方向。光學微影製程在近年來受到了相當程度的挑戰，原因在於光學微影的特性會受到繞射極限的影響，導致微小化技術上受到限制。也因此開始有科學家研究能代替光學微影的微小化技術，而在多項次微米研究中，表面電漿子透鏡(surface plasmonic lens, SPL)中的突破光學繞射極限理念更是吸引眾多科學家的關注，且對於表面電漿的性質研究也逐步確立。
本論文主要內容為表面電漿子透鏡的設計與製備以及將其應用於直寫微影實驗中。採用有限時域差分演算法模擬電磁場分佈的方式，研究設計以多環同心圓圖型作為表面電漿子透鏡之微結構設計方向，並探討其材料與結構參數的改變對聚焦點特性之影響。依照模擬設計的結構與材料參數，將表面電漿子透鏡分為三個主要製作步驟，依序為經由熱蒸鍍鍍上200 nm的銀金屬薄膜，再以聚焦離子束微影製程製作最外環直徑30 μm、狹縫間距1.5 μm以及縫寬度200 nm的五環同心圓結構，最後以電漿化學氣相沉積製作出一厚度為1 μm的防硫化與氧化之二氧化矽薄膜。並以此設計之表面電漿子透鏡作為直寫微影中的聚焦透鏡，分別以點與一維直線的微影實驗，探討此透鏡之實際聚焦特性，並以最佳一維直線的直寫微影參數，製作二維矩形結構，最終以本論文設計的五環同心圓結構之表面電漿子透鏡，利用直寫微影方式成功以一800 nm左右的次微米線寬製作出二維正方形結構。

關鍵字

表面電漿子透鏡 ； 直寫微影

並列摘要

The extreme small linewidth is a big challenge of optical lithography due to the limitation of optical diffraction. Many studies were proposed to improve the linewidth, surface plasmonic lens (SPL) is a planar lens that can narrow the spot size by the constructive interference of electromagnetic wave generated from surface plasmon resonance (SPR). This study is the design and fabrication of surface plasmonic lens and its application on direct-write lithography. Finite-Difference Time-Domain (FDTD) method was used to simulate the electromagnetic field when the laser passes through the surface plasmonic lens with the multiple concentric annular rings. The material (such as metal and dielectrics) and structural parameters (such as circle diameter, slit width, slit radius and number of rings) were discussed to understand their influences on the optical focusing properties. The fabrication of the surface plasmonic lens was based on the simulation results, the thermal evaporator was used to deposit silver thin film with 200 nm thick. Focused ion beam was used to produce 5 annual rings with 500 nm slit width and1.5 μm ring spacing. The chemical vapor deposition (CVD) was used to fabricate a SiO2 passivation film with 1 μm thick. The surface plasmonic lens was applied on the lithography process. The light source is an UV laser with 405 nm wavelength at 28.876 mW power. The photoresist is SU-8 (TF6000.5) with 400 nm thick. A square with 50 μm* 50 μm and 800 nm linewidth was successfully produced.

並列關鍵字

Surface Plasmonic Lens ； Direct-Write Lithography

參考文獻

參考文獻

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