本研究發展一種利用奈米壓印技術搭配背向式曝光的製程，在石英基板上製作出雙層且圖案為互補的次微米金屬結構，並解決過去所發表的文獻中遇到的製程瓶頸，包含了使用電子束微影技術使得製程速度較慢、元件面積較小，使用電子束蒸鍍使光阻結構側壁沾附金屬等。同時以實驗探討將此製程應用於製作雙層互補式電漿子超穎表面 (Plasmonic meta-surfaces) 的可能性。
在本研究的實驗中，會以次微米等級的直線光柵 (Linear grating) 結構之模具進行熱壓成形奈米壓印，搭配後續製程於石英基板上定義出金屬圖案，之後覆蓋上一層二氧化矽之平坦化介電層，再利用此金屬層作為光罩，以背向式曝光的方法，對上層光阻進行曝光。本論文探討曝光參數、曝光距離、金屬圖形對於光阻形貌的影響，最後找出最佳的製程參數與實驗方法，並以此在介電層上定義出第二層金屬的圖案，完成雙層金屬結構。
在實際的應用方面，將利用本研究所開發的製程，製作出文獻中所設計的非對稱光傳輸元件結構，並利用光譜儀對樣品進行量測，最後與文獻中的光學效果進行比對與驗證。

This study aims at developing a nanofabrication process using nanoimprint lithography (NIL) along with backside exposure to fabricate bi-layer complementary sub-micron metal structures on a quartz substrate. The main objective is to overcome several processing limitations reported in previous literature, which include slow fabrication speed and smaller device area due to the use of electron beam lithography, as well as metal adhesion on the resist structure sidewalls when employing electron beam evaporation. Additionally, the feasibility of applying this process to fabricate bi-layer complementary plasmonic meta-surfaces will be investigated through experiments.
In the experimental setup, standard nanoimprint lithography will be conducted using a sub-micron linear grating mold to define the metal pattern on a quartz substrate. A flat silica layer will be deposited as a planarizing dielectric layer, and the metal layer will serve as the mask for backside exposure of the top resist layer. Various exposure parameters, exposure distances, and metal patterns will be investigated to determine their impact on the resist morphology. The optimized process parameters and experimental approaches will be used to define the second-layer metal pattern on the dielectric layer, which completes the bi-layer metal structure.
For practical applications, the developed process will be utilized to fabricate a designed asymmetric light transmission device reported earlier in the literature. The fabricated samples will be characterized using optical spectrometer and the optical effects will be compared and validated against those reported in the literature.

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