本研究利用聚苯乙烯奈米球微影術（Polystyrene Nanosphere Lithography, PS NSL）結合金催化選擇性化學蝕刻法，成功地在(001)矽基材上製備出大面積垂直排列且可調變長度之矽晶奈米柱陣列，並對矽晶奈米柱之晶體結構及反應動力學作深入探討。實驗中也將探究水滴在表面生成奈米柱結構的試片上之潤濕行為及其光學性質之變化。
由掃描式電子顯微鏡（SEM）及穿透式電子顯微鏡（TEM）觀察可發現，金屬催化選擇性蝕刻所生成之奈米柱不但具有相當好的均一性，且與實驗所用之奈米球模板之直徑相當吻合，其奈米柱寬度約為126 nm。而從TEM影像及其相對應之電子繞射圖形分析鑑定可得知本研究所製備之矽晶奈米柱均為單晶結構，且軸向方向沿著[001]方向生成。此外，藉由一系列SEM橫截面影像觀察，可獲得不同反應溫度及時間下矽晶奈米柱之生成長度變化。藉由量測不同反應溫度下奈米柱之生成速率，可由阿瑞尼士（Arrhenius）關係圖中求得其生成反應活化能約為76.7（kJ/mole）。
經水滴接觸角實驗觀察與分析結果發現，表面生成矽晶奈米柱陣列之試片經HF清洗後呈現相當高的疏水性，其接觸角可達125°-150°，此種因表面奈米柱結構造成接觸角提升的現象可用Cassie Model解釋。利用紫外光-可見光光譜儀分析反應後試片可發現，表面具有奈米柱陣列結構的試片在可見光波長範圍內（400-800 nm）呈現相當低的反射率（﹤5％）。

In the present study, we have demonstrated that large-area, length-tunable arrays of vertically aligned Si nanorod arrays were successfully produced on (001)Si substrates by using the PS nanosphere lithography combined with the Au-assisted selective chemical etching process. The crystal structures, formation kinetics, surface wetting behaviors, and optical properties of the Si nanorods produced have been investigated.
The SEM and TEM examinations revealed that the diameter of the Si nanorods produced was very uniform and observed to be approximately 126 nm, corresponding to that of RIE-reduced PS sphere mask used. Based on the analyses of the TEM image and the corresponding SAED pattern, it can be concluded that all the produced Si nanorods were single crystalline and the Si nanorods formed along the [001] direction. After a series of cross-sectional SEM examinations, the length variations of Si nanorods produced with etching time for various reaction temperatures were obtained. By measuring the formation rates of Si nanorods at different reaction temperatures, the activation energy for the linear formation of Si nanorods could be determined from an Arrhenius plot to be about 76.7 kJ/mole.
The results of the water contact angle measurements indicated that the surfaces of HF-treated Si nanorod arrays exhibited strong hydrophobicity with water contact angle of 125°-150°. The hydrophobic behavior of the HF-treated Si nanorods was discussed in the context of the Cassie model. The UV-Vis analysis results indicated that Si substrate with Si nanorod arrays exhibited low reflection properties (﹤5％) over the visible light range (400-800 nm).

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