本研究以純矽基板為材料，利用紅外光（Infrared, IR）與紫外光（Ultraviolet, UV）飛秒雷射進行表面微結構加工，探討雷射波長、MOD加工條件、掃描間距及結構形式對表面形貌、反射率與光熱性能之影響。實驗首先比較不同波長及MOD條件所形成的一維平行結構，再進一步設計UV/IR混合結構與二維交叉結構，藉由改變加工方向與縮小掃描間距，提高表面的加工覆蓋程度。加工後利用光學顯微鏡（OM）、掃描式電子顯微鏡（SEM）及原子力顯微鏡（AFM）觀察表面形貌，並進行反射率與光熱量測。最後於雷射加工後之矽基板表面鍍製氮化鈦（Titanium Nitride, TiN）薄膜，透過水蒸發實驗評估不同結構於光熱應用下的實際表現。
實驗結果顯示，不同雷射加工條件會形成不同尺度的溝槽、粗糙區域及微細結構，而增加加工方向或縮小掃描間距後，可減少表面未加工的平坦Si區域，使反射率進一步下降。未加工Si基板平均反射率約為35%，其中二維UV1250於0.02 mm掃描間距下可降至7%，鍍製TiN後進一步降至6%，為本研究最低量測值。TiN鍍膜後多數試片亦呈現反射率下降及表面溫度提高的情形，顯示雷射表面結構與TiN薄膜可共同影響試片的光學與光熱表現。
光熱與水蒸發結果則發現，反射率降低並不一定會持續提升表面溫度與蒸發速率。以一維UV1250為例，掃描間距由0.04 mm縮小至0.02 mm後，反射率雖進一步降低，但表面溫度與蒸發速率反而下降；相較之下，二維UV1250於0.04～0.02 mm間仍維持相近的高光熱與蒸發表現。2D UV1250 0.02 mm搭配TiN後最高表面溫度可達61.7°C，蒸發速率為1.7845 g/h，而0.04 mm/TiN亦具有相近的量測結果。
由本研究結果可知，提高雷射加工覆蓋程度有助於降低矽表面反射率，但實際光熱與水蒸發性能仍受到表面形貌、結構形式及熱量傳遞情形影響。

This study examined how femtosecond laser processing and titanium nitride (TiN) coating affect the optical, photothermal, and water evaporation performance of silicon. Infrared and ultraviolet (UV) lasers were used to fabricate parallel, orthogonal, and hybrid structures at different modulation frequencies and scan pitches. Surface morphology, reflectance, dry surface temperature, and evaporation rate were compared before and after coating. Mean reflectance was evaluated over 900-1000 nm. Laser texturing reduced reflectance, while TiN generally increased temperature and evaporation rate. The TiN-coated two-dimensional UV1250 structure at a 0.02 mm pitch exhibited 6% mean reflectance, a surface temperature of 61.7 °C, and an evaporation rate of 1.7845 g/h under 800 W/m² halogen illumination. This rate exceeded the pure-water reference by 16.94%. However, its performance was close to that at 0.04 mm. For one-dimensional UV1250 structures, reducing the pitch from 0.04 to 0.02 mm lowered reflectance but also reduced temperature and evaporation rate. These results demonstrate that the lowest reflectance does not necessarily identify the best photothermal processing condition. Changes in heat distribution and dissipation provide a possible explanation, although the specific thermal pathways require further verification.

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