本研究主要探討飛秒雷射誘導表面週期性結構(Femtosecond Laser Induced Periodic Surface Structure,簡稱FLIPSS)之特性，分別針對STAVAX模具與其鍍鎳模具表面，透過調整適當的雷射功率(雷射能量密度)、脈衝重複率以及掃描速度，製作出具有不同形貌與週期的微奈米結構，後續結合射出成型轉印與熱壓印技術，分別對厚度為2 mm的聚甲基丙烯酸甲酯(PMMA)與環烯烴共聚物(COC)板材進行結構轉印，並量測其反射率與穿透率，探討FLIPSS的光學性質(穿透率與反射率)。此外，本研究亦推導出FLIPSS現象簡化的數學模型，藉此了解雷射加工參數與結構週期的關係，並探討其表面結構成形的過程與物理機制。
研究結果顯示，飛秒雷射誘導表面週期結構技術其雷射加工參數與結構週期大小之關係，其結果大致分成兩種形態，一種主要由雷射的脈衝重複率決定，其週期結構隨著雷射的脈衝重複率越高而週期有越來越短的趨勢；另一種則主要由雷射的脈衝能量決定，隨著雷射脈衝能量越低而變小。此外，結構週期形態也會隨著雷射功率的大小與掃描速度的不同而有變化，其結構型態大致可分成兩種，一種單純只有垂直雷射掃描方向的週期結構，其雷射能量密度較低，掃描速度較快，結構週期約為900 nm；另一種週期結構則同時存在平行與垂直雷射方向的兩種週期結構，其雷射加工表面能量較高，掃描速度較慢，結構週期約為2 - 5 µm。
STAVAX模具透過FLIPSS技術加工處理完成後，結合熱壓印與射出成形轉印技術，可成功在PMMA與COC平板上轉印出大面積( 8 mm × 8 mm )的表面週期性結構。其中具有FLIPSS之PMMA板，在可見光波段的反射率可降低3 - 4%；但是具有FLIPSS之COC板在可見光波段的直接穿透率則降低10 - 50%。未來研究目標期望透過此技術，可快速大量翻印具有功能性的週期結構與週期小之高分子材料，以期能改進現有的微奈米轉印製程。

The purpose of this thesis is to experimentally generate periodic surface structures on the metal substrate (Both STAVAX stainless mold and Ni-coated STAVAX stainless mold) by femtosecond laser-induced periodic surface structure (FLIPSS) technique. First, a structured metal template was fabricated by femtosecond laser with proper laser fluence, repetition rate, and scanning speed by Ytterbium femtosecond laser system. After the template had been fabricated, it was used as a mold to transfer structure to the polymer plate by sub-micro imprinting method, then the plate’s reflectance and transmittance was measured in visible light region.
As the result, FLIPSS’s period can mainly dependent on fs-laser fluence and number of pulses. The period will become smaller as number of pulses increase and laser fluence decrease. Besides, the structure profile can also be changed with fluence and scanning speed. The structure types can be divided into two types. One only has the direction perpendicular to scanning direction. The structure is formed by lower fs-laser fluence and slower scanning speed with the period close to 900 nm. Another has both perpendicular and parallel directions. Furthermore, the formation of the structures can be determined by higher laser fluence and lower scanning speed with the period from 2 to 5 μm.
Combination of FLIPSS and sub-micro imprinting method (including hot-embossing and injection molding) can successfully transfer the periodic structures to polymer template in an area of 8 mm by 8 mm. FLIPSS on PMMA plate can reduced reflectance about 3 to 4 % in visible light region, but FLIPSS on COC plate unfortunately reduce the transmittance about 10% to 50% in visible light region.
The future prospect of this research is promising to rapidly transfer functional sub-microstructure with smaller period on polymer. Hoping FLIPSS technique can improve the process of imprinting or other industrial applications.

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