本論文包含兩部份的研究內容：一是利用準分子雷射加工，搭配繞射式灰階光罩，製作做出微米級的三維立體結構，應用於高分子材質的光波導元件；二是以奈米壓印製程技術製作奈米結構，應用於超穎介面的光學元件，並探討後續量產製作超穎介面的可行性。
在微米級光波導元件的研究中，重點在於發展「面外微鏡耦合」 (Out-of-plane Micro-mirror Coupling) 技術，關鍵是如何在已經完成的高分子光波導結構上，利用準分子雷射與灰階光罩的加工特性，一次性地製作出正45°斜率、結構尺寸約45 微米的微反射鏡；研究重點在於如何維持加工後45°傾斜面的平整性，以增強光波導的光耦合效率。雷射加工後的結構經由共軛焦顯微鏡的量測結果，其45°斜率角度的誤差不超過 ± 1°，表面粗糙度最小值為155 nm；而光耦合效率的實驗量測結果約為23%。在奈米級光學結構製作方面，主要是針對具有共振腔效應的超穎表面，在玻璃基板上製作出三層圖案化的金屬奈米結構，每一層金屬結構間則為玻璃材質的介電層。此一共振腔效應的超穎表面可利用電磁波的異常穿透特性，達到操控電磁波波前的能力，產生諸如波束偏折、波束聚焦、分光、…等光學功能。三層金屬結構中的第一與第三層是互相垂直的奈米金屬光柵，作為偏振片使用；第二層金屬結構則是依不同的光學目的設計出不同的陣列式圖案，以產生偏振轉換。金屬結構的高度為80 nm，特徵尺寸約在100 到數百nm 之間，金屬結構層之間的玻璃介電層的厚度為200 nm。
超穎介面之奈米結構的製作方法是利用雙阻劑與熱壓成形的奈米壓印技術，這能夠使本研究在模具深度150 nm的限制下，得以完成80 nm厚度的金屬結構高度。但是在第一與第三層的奈米光柵部份，受限於乾式蝕刻的側蝕效應，金屬結構高度只能達到45 nm，導致在偏振轉換的效率量測上只有8 %左右。未來可以努力的解決對策有：提高模具深度、找出不會側蝕結構側壁的乾式蝕刻參數、或改善金屬舉離製程、…等等。

This paper consists of two parts: excimer laser micromachining of micro-scaled three-dimensional (3D) microstructures applied to polymer optical waveguides, and nano-imprinting lithography for fabricating nanostructures with applications on metasurfaces.

For the excimer laser micromachining of 3D microstructures, the goal is to fabricate inclined micromirrors with a positive 45° slope. These inclined micromirrors are directly fabricated on a polymer optical waveguide using excimer laser along with a gray-scaled mask projection method. The dimension of the fabricated micromirror is around 45 micron and the key issue is to maintain its surface flatness and smoothness. Examination on the machined micromirrors shows the angular error is within 1 degree and the minimum surface roughness is around 155 nm. Finally, the light coupling efficiency using the 45° inclined micromirror along with a polymer optical waveguide is around 23 % by experimental measurement.

In the research of nanostructures, metasurfaces based on the resonant cavity effect are investigated. The metasurfaces are fabricated on a glass substrate and consist with three layers of patterned metallic nanostructures separated by dielectric layers. The three-layer nanostructure uses the characteristics of abnormal penetration of electromagnetic waves to manipulate the electromagnetic wavefront, which can result in certain optical properties such as beam deflection, beam focusing, light splitting, …etc. The first and the third layers are metal nano-gratings that are perpendicular to each other and used as polarizers; while the second layer metallic nanostructures are composed of different arrays of designed patterns for polarization conversion. The height of the metal structure of each layer is 80 nm, and the three layers of metallic nanostructures are separated by two layers of spin-on glass (SOG) with a layer thickness of 200 nm.

The method for fabricating the nano-scaled metal structures is using hot embossing nanoimprint lithography along with double resist layers, which can achieve 80 nm in the height of metal nanostructures even when the depth of the imprinting mold is limited to 150 nm. Experimental results and measurements show the dimensional deviation of the patterned nanostructures is within ± 0.1 %, and the height of the second layer metal structures also reached 80 nm. However, the structural height of metal nano-gratings on the first and the third layers could only reach 45 nm, due to the dry etching processes during nanoimprinting. Therefore, the efficiency measurement of polarization conversion is only about 8%. Future effort in improving this fabricating technology is under investigation.

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