矽基奈米結構具有許多優異的性質，廣泛應用於半導體、光電、生醫及能源領域中，因此發展製程技術扮演著關鍵的角色。本研究為探討一種簡易與迅速的金屬輔助化學蝕刻法，其方式不同以往的固-液-氣法與電化學蝕刻法，可在常溫與常壓條件下，利用自發性的電化學反應，即可生成出大面積且均勻的矽基奈米結構。為探討以此反應所成長矽基奈米結構，於不同金屬層、厚度、矽基材阻抗、蝕刻液及反應時間等參數下進行生成反應，而藉由電子顯微鏡觀察矽奈米結構的表面形貌、影像的分析及量測孔隙率等性質討論。經一系列實驗後發現，金屬的種類將會影響蝕刻速率，當反應的金屬薄膜厚度增加，結構將由奈米孔洞狀逐漸轉變為獨立且均勻分佈的奈米線與片狀結構。在此，為了達到更簡易、迅速性及低成本優勢，於矽表面以無電鍍技術來達到沉積金屬層，藉由金屬奈米粒子的變化可得到更細小及緻密的孔狀、片狀與線柱狀奈米結構產物，更增加其實際應用的可能性。

In recent years, silicon nanostructures have received great deal of attention from it is unique surface effects. The use of silicon nanostructures have been applied to a wide variety of fields including semiconductor, optoelectronic, biological and energy field. Therefore, developing silicon nanostructure fabrication technique becomes an intriguing topic for researchers. A fast and simple fabrication method called metal-assist chemical etching was investigated in this thesis. Compare with other silicon nanostructure fabrication techniques such as the solid-liquid-gas and electrochemical etching, metal-assist etching is a spontaneous electrochemical reaction which can uniformly create large area silicon nanostructure in room temperature and atmosphere conditions. In order to effectively control the growth of silicon nanostructure, effects of process parameters such as metal layer, substrate resistivity, etchant composition and etching time are investigated. SEM images are taken to characterize the silicon nanostructure morphologies. We found that the metal layer have significant effects to the silicon nanostructure formation. When the metal thickness increases, the nanostructures change from nanopores to nanofilaments or nanowires. In order to have simpler, faster and lower cost fabrication process, we further developed an electroless plating method to deposite the metal layer on silicon surface. In this thesis, we successfully demonstrate that finer silicon nanostructure can be fabricated through the electroless plating approach which holds great commercial potential from its simple, fast and low cost advantages.

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