一維矽基奈米結構由於高深寬比而擁有優異的性質，已有各式製程手法相繼被提出。近年來，一種成本低廉、製程簡單結合聚苯乙烯奈米球微影術與金屬催化化學蝕刻法在不同矽晶圓上製備大面積規則準直排列的矽晶奈米線與奈米柱陣列已經引起注意。然而，目前針對奈米管的製備相對於奈米線結構而言較為複雜且困難。由多篇文獻中指出，內外雙層且中空的奈米管結構能夠表現出比奈米線更加優異的性質。因此，本研究提出一種經氧氣電漿修飾的聚苯乙烯奈米球微影術搭配純金催化化學蝕刻的新穎製備技術，可在室溫下於(001)Si基材上製備出大面積規則準直排列的單晶矽奈米洞與奈米管陣列結構。 實驗結果顯示，本實驗製備出的單晶矽奈米管陣列其晶面取向與原始所使用的(001)Si基材相同，且藉由調整使用的奈米球粒徑大小與純金蝕刻參數可以分別調控奈米管的間距與內徑。另外，從掃描式電子顯微鏡影像觀察發現，奈米管的長度隨著純金催化化學蝕刻時間呈線性增加，表示其生成為反應控制機制。而由水滴接觸角與紫外光、可見光光譜儀量測結果顯示出，奈米管相較於奈米線結構擁有更加優異的表面疏水性質與光學抗反射性質。綜合以上結果得知，本研究所提出的新穎製備手法相信將能夠進一步運用在各式單晶矽基材上，成功地製備出不同尺度之矽基奈米管陣列結構。 ;One-dimensional (1D) silicon-based nanostructures have excellent properties due to their high aspect ratio. There are several synthetic techniques have been proposed. Recently, a low cost method, which is based on the polystyrene nanosphere lithography and metal-assisted catalytic etching process has attracted much attention. By using this technique, large area, well-ordered and vertically-aligned Si nanowires and Si nanorods can be readily produced on different types of Si wafers. However, compared with the fabrication processes of Si nanowires, the fabrication of Si nanotubes are relatively complex and difficult. Many recent studies have demonstrated that 1D nanostructures with hollow interiors have better properties than their solid counterparts. Therefore, in this study, we proposed a new and facile route for fabricating large area, well-order arrays of Si nanoholes and vertically-aligned single-crystalline silicon nanotubes on (001)Si substrates at room temperature by using the O2-plasma modified nanosphere lithography in conjunction with the Au-assisted chemical etching processes. The experimental results reveal that all the produced Si nanotubes are single-crystalline and their axial orientation is the same as that of the (001)Si substrate. The sapcing and interior diameter of the Si nanotubes can be tuned by adjusting the diameter of nanospheres and the Au etching conditions. It is also found from SEM observations that the length of the Si nanotubes increase linearly with the Au-catalyzed etching time, indicating that the formation process is reaction controlled. The results of water contact angle and UV-vis spectroscopic measurements clearly show that, compared with Si nanowires, the produced Si nanotubes exhibit higher hydrophobicity and better antireflection properties. The obtained results present the exciting prospects that the new approach proposed here provides the capability to fabricate other Si-based nanotube arrays on various Si substrates.
