氣體電漿表面改質及濕式化學蝕刻法結合微奈米球微影術製備位置、尺寸可調控矽晶二維奈米結構陣列之研究

Fabrication of Site- and Size-controllable Periodic Arrays 2D Well-ordered Si Nanostructures by Plasma Modified Nanosphere Lithography and Chemical Wet Etching Processes

林耀星(Yao-hsing Lin)

指導教授 ： 鄭紹良

國立中央大學/工學院/化學工程與材料工程學系/碩士(2012年)

摘要

本研究成功地利用奈米球微影術結合氣體電漿表面改質及非等向性鹼性溶液蝕刻技術在不同晶面指向之矽單晶基材上製備出密度、尺寸及形狀均可控制之規則有序排列矽基奈米結構陣列，並以SEM、AFM、TEM、SAED、EDS、XPS、UV-Vis及C.A.有系統地進行表面形貌、晶體結構、成分組成分析鑑定及光學和表面性質之量測。
在規則有序矽晶奈米孔洞陣列之製備方面，本研究利用氧氣電漿以反應性離子蝕刻方式調變出PS球奈米模板之球徑大小，並同時以經氧氣電漿處理後於矽晶基材上所生成非晶氧化矽層作為蝕刻遮罩，調變氫氧化鉀蝕刻時間後，成功地於各式矽單晶基材上製備出形狀、尺寸及位置皆可調變之矽晶奈米孔洞陣列。
另一方面本研究也結合奈米球微影術、氣體電漿表面改質或金屬矽化反應和選擇性化學蝕刻製程成功在(001)、(110)、(111)矽晶基材上製備出大面積，尺寸及高度皆可調變之規則有序矽晶奈米錐陣列。
經一系列不同尺寸矽晶奈米孔洞及奈米錐陣列試片之水滴接觸角量測發現，表面具有奈米結構陣列之矽晶試片其接觸角呈現不同程度之疏水特性，此現象可用Cassie Model來解釋。此外，以紫外光-可見光光譜分析可發現矽晶表面有奈米結構陣列時矽晶基材具有光捕捉效應，可大幅降低光之反射率。

關鍵字

溼式蝕刻 ； 矽晶孔洞 ； 矽晶錐 ； 電漿處理 ； 奈米球微影術

並列摘要

The present study has demonstrated the successful fabrication of density-, size- and shape-controllable Si nanostructure arrays on Si substrates of different orientation by using plasma modified nanosphere lithography and anisotropic wet etching process. The morphologies, crystal structures, compositions, optical and surface properties of the Si nanostructure arrays produced have been systematically investigated by SEM, AFM, TEM, SAED, EDS, XPS, UV-Vis and contact angle analyses.
For the fabrication of periodic Si nanohole arrays, we take advantage of O2 plasma RIE treatment, which allows us simultaneously to adjust the diameter of PS nanospheres template and to form a passivation a-SiOx layer on Si serving as the etching mask. The shapes, sizes and positions of Si nanoholes that formed on Si substrates could be tuned by adjusting the diameters of the colloidal nanospheres and the KOH etching time. On the other hand, by combining the plasma modified nanosphere lithography, selective chemical etching process or metal silicide formation, large-area, size- and height-tunable Si nanocone arrays were also successfully fabricated on (001), (110) and (111)Si substrates in this study. From the water contact angle measurements, the surface of HF-treated Si nanohole and nanocone arrays exhibited hydrophobic characteristics. The hydrophobic behavior of Si nanostructures could be explained by the Cassie model. Furthermore, UV-Vis spectroscopic measurements revealed that the nanostructured Si surfaces exhibit strong antireflection properties.The enhanced antireflection properties can be attributed to the light trapping effect resulting from the nanostructure-arrayed Si surfaces.

並列關鍵字

plasma treatment ； nanosphere lithography ； wet etching ； silicon holes ； silicon cones

參考文獻

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