物理氣相沉積（PVD）是一種廣泛使用的金屬鍍膜技術，適用於沉積後續金屬薄膜電鍍製程的晶種層。然而，物理氣相沉積是一種昂貴且需要真空的過程，並且對於高深寬比多孔結構的填充能力較差。相較之下，無電鍍沉積具有比物理氣相沉積更快的沉積速率、易於處理、低成本等優點。本研究的目的是通過在陽極氧化鋁（AAO）模板上沉積無電鍍鎳種子層作為後續電鍍銅的背電極，以優化電鍍奈米雙晶銅奈米線的製程。在經兩階段擴孔製程後的 AAO 模板進行無電鍍鎳沉積，發現有鎳顆粒鑲嵌在 AAO模板孔壁中，使後續沉積的奈米銅導線晶相成長較不規則，變成具有較低 (111) 生長織構係數（TC(111) = 1.64）的多晶結構。通過調整AAO模板的擴孔製程，無電鍍沉積鎳在AAO孔壁上的鎳顆粒可被移除，後續電鍍沉積銅奈米線的 (111) 生長織構係數可大幅提升（TC(111) > 2.6），並具有高密度奈米雙晶結構。此研究也探討電流密度對於奈米銅導線晶相和微結構的影響。在適當地電流密度施加條件下，可以合成出具有高密度雙晶結構的銅奈米線，而在施加低和高電流密度下，前期會先以 (111) 方向成長，中後期則轉為 (220) 方向成長。本研究中的全濕式化學製程所製備之雙晶結構銅奈米線有機會可應用於電化學二氧化碳還原中的觸媒材料。

Physical vapor (PVD) is a widely used deposition technique to deposit thin seed layers for subsequent electrodeposition of metal films. However, the PVD is an expensive vacuum-based process and has poor filling capability for high aspect-ratio porous structures. Alternatively, electroless plating provides several advantages over the PVD such as fast deposition rate, facile process, low cost, and conformality. The objective of this work is to develop a simple and time-saving process to prepare electroless plated Ni seed layer on an anodic aluminum oxide (AAO) membrane in order to electrodeposit nanotwinned copper nanowires (nt-CuNWs) subsequently. Following a typical two-step pore widening process, it was found that some nickel particles were embedded inside the AAO pores, which affected the subsequent AAO-templated CuNWs electrodeposition. The electrodeposited CuNWs showed a polycrystalline microstructure with a relatively low (111) growth texture (TC(111) = 1.64). By adjusting the pore widening process, the nickel particles in the AAO pores were removed, and the electrodeposited CuNWs exhibited a high (111) growth texture (TC(111) > 2.6) along with dense nanoscale twin structures. The influence of electrodeposition current density on the crystallography and microstructure of the electrodeposited CuNWs was investigated. CuNWs with highly dense twin boundaries were discovered at a medium applied current density, while a (220)-dominated growth texture was found at both low and high current densities applied. The all-wet chemical process presented in this study shall be beneficial for preparing nt-CuNWs as CO2RR catalytic materials.

摘要-----------------------------------------------------------I
Abstract------------------------------------------------------II
誌謝----------------------------------------------------------III
Contents------------------------------------------------------IV
Content of Figures--------------------------------------------VI
Content of Tables---------------------------------------------IX
Chapter 1 Introduction-----------------------------------------1
1.1 Research Background----------------------------------------1
1.2 Electroless Plating----------------------------------------1
1.3 Motivation-------------------------------------------------2
Chapter 2 Literature Review------------------------------------4
2.1 Nanotwinned Copper Nanowires-------------------------------4
2.1.1 Nanotwinned Copper Structure-----------------------------4
2.1.2 Template-Assisted Electrodeposited Metal Nanowires-------11
2.2 Electroless Plating----------------------------------------18
2.2.1 Solution Components--------------------------------------18
2.2.2 Plating Mechanism----------------------------------------19
2.2.3 Plating Process------------------------------------------20
2.3 Electroless Nickel Plating---------------------------------21
Chapter 3 Experimental Section---------------------------------30
3.1 Experimental flow------------------------------------------30
3.2 Chemicals and Apparatuses----------------------------------31
3.3 Specimen Preparation---------------------------------------32
3.4 Analysis Techniques----------------------------------------34
3.4.1 X-ray Diffractometer (XRD)-------------------------------34
3.4.2 Field-Emission Scanning Electron Microscope (FE-SEM)-----35
3.4.3 Transmission Electron Microscopy (TEM)-------------------35
Chapter 4 Results and Discussion-------------------------------36
4.1 Process Optimization of AAO Templates----------------------36
4.1.1 AAO template with Electroless Ni(P) Back Electrode Coating- 36
4.1.2 AAO Pore Widening Process--------------------------------37
4.2 Effect of Current Densities on Copper Nanowires Growth Texture-42
4.2.1 Microstructure of Electrodeposited Cu Nanowires----------42
4.2.2 Texture of electrodeposited Cu nanowires-----------------47
Chapter 5 Conclusions------------------------------------------50
5.1 Conclusions------------------------------------------------50
5.2 Future Work------------------------------------------------50
References-----------------------------------------------------52

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