本論文利用奈米壓印製程技術製作金屬奈米結構，並應用於具有電漿共振效應的超穎表面(Metasurface)。研究主題為三種不同功能的超穎表面，分別為：單元結構(Unit cell)或半波片(Halfwave plate)、梯度板(Gradient Metasurface)、以及超穎透鏡(Metalens)，透過不同製程來提升其效率以及其光學性質，並探討後續大量製作之可行性。上述三種元件已能分別能顯示出偏振轉換、光束偏折、以及聚焦的光學特性，且其效率已有相當明顯的改進；例如，半波片的量測效率已經可以達到70 %左右。本研究主要針對具有共振腔效應的超穎表面，在2吋玻璃基板上製作出三層金屬結構，並且包覆三層高度為200 nm玻璃材質的介電層。三層金屬結構分別為第一、三層為奈米金屬光柵的偏振片，且其方向相差90度，模擬的最佳線寬為100 nm、週期為200 nm，且金屬高度為40 nm。第二層金屬結構則是針對上述三種不同元件而有不同之設計，所採用之金屬層的高度有40 nm以及60 nm 二種。本實驗透過不同製程改變中間層金屬高度(40 nm、60 nm)來量測其最佳效率，並與模擬結果相互驗證。此外，本研究也利用金屬側壁蝕刻法突破在壓印模具高度受限的情況下，製作出傳統舉離製程無法達到的金屬高度。

This thesis applies nanoimprint lithography and technology to fabricate metallic nanostructures which are applied to plasmonic metasurfaces. Three types of metasurfaces with different optical functions are fabricated and investigated, which are unit cell (or halfwave plate) structure, gradient metasurface, and metalens. various fabrication processes are tested and studied to improve their efficiency and optical properties, as well as to explore the feasibility of mass production in the future. Significant improvement has been achieved, for example, the efficiency of halfwave plate is reaching 70 % of its theoretical value. The metasurfaces which utilize the resonant cavity effect are basically a three-layer metallic nanostructures fabricated on a 2-inch glass substrate and sandwiched with three 200 nm thick dielectric layers. In the three-layer metallic nanostructure, the first and third layers are linear grating polarizers which are mutually perpendicular to each other. The simulated optimal line width is 100 nm, the period is 200 nm, and the metal height is 40 nm. The second layer metallic nanostructures have different designs for the above-mentioned optical functions, with two different metal layer thicknesses of 40 nm and 60 nm. Experiments have been conducted by changing the metal layer thickness using different fabrication processes, and cross examining their measured efficiency with simulation results. Additionally, this thesis also developed a metal sidewall etching method which can significantly increase the structural height of the fabricated metallic nanostructures.

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