透明導電薄膜為許多光電元件的關鍵零組件。氧化銦錫 (indium tin oxide, ITO) 因為兼具低片電阻 ( < 10 Ω/sq) 與高透光度 ( > 90 T%) 而成為目前透明導電膜最主要的材料系統。但是隨著可撓式電子產品的發展，真空製程濺鍍生產效率難以提升、塑膠基板鍍膜困難度高且機械性質硬脆的氧化銦錫將面臨被淘汰的可能。尋找下一世代透明導電薄膜材料變成一件勢在必行的事情。在許多相近的競爭技術中，使用銅奈米線所製備的透明導電薄膜具有相當的開發潛力。銅奈米線具備良好的導電率與延展性，而且在銅奈米線導入奈米雙晶結構 (nanotwin structure) 可以有效提升機械性質，同時維持良好的導電特性。此外，銅內部的雙晶結構也被發現能夠遲滯電遷移的現象，進而延長元件的使用壽命。綜合上述優點，奈米雙晶銅無疑是優異的導線材料。但是銅奈米線表面生成之氧化物易造成導電薄膜元件片電阻上升或是可靠度下降等問題。
本實驗以模板輔助低溫脈衝電鍍製備出奈米雙晶銅奈米線。為提高銅奈米線的抗氧化能力，本研究成功開發以伽凡尼置換反應均勻沉積銀殼層至銅奈米線表面的技術。除利用穿透式電子顯微鏡分析銅奈米線與銀殼層微結構外，並利用四點探針量測單根奈米線的電阻，分析銀殼層對於銅銀核殼奈米線導電性質的影響。最後則是利用抽濾轉印的方式將奈米線製備成透明導電膜，透過調控不同轉印壓力以最佳化透明導電膜製程。所製備出銅銀核殼結構奈米線透明導電薄膜之片電阻為41 Ω/sq，透光度為88.9 T%，其 Figure of merit 可達70，並且在85度高溫環境下持續觀察300小時後仍維持良好導電性。此結果說明銀殼層能有效保護內部銅線不受氧化。另外，在經過1000次的循環撓曲條件下，薄膜片電阻值仍沒有改變，顯示銀殼層並不影響奈米線的可撓性。綜合上述結果，銅銀核殼結構奈米線具有極佳的化學穩定性，能夠幫助提升奈米線透明導電薄膜之性能與可靠度。

Transparent conductive films (TCFs) are essential components in many optoelectronic devices. Indium tin oxide (ITO) that possesses high transmittance ( > 90 T%) and low sheet resistances ( <10 Ωsq−1 ) has been widely employed in TCFs. The development of flexible electronic devices drives the need of the TCFs on flexible substrates. However, the brittleness of ITO and the low throughput of the vapor-phase sputtering process on plastic substrate restricted the applicability of ITO on the flexible electronic devices. Looking for alternatives to the next-generation TCFs becomes imperative. Cu nanowires (NWs) have become a promising alternative solution for TCFs by forming a NW network on a transparent substrate. Cu NWs have superior electrical conductivity and flexibility. Nano-twinned Cu NWs have exhibited high mechanical strength, good conductivity, and moreover, superior electromigration resistance, which can be an excellent material to the NW-based TCFs. Still, the sheet resistance of Cu NWs films can easily increase due to the formation of copper oxides and leads to a severe reliability issue.
In this study, Cu NWs were synthesized by pulsed electrodeposition with porous anodic aluminum oxide (AAO) templates at low temperature. To improve their anti-oxidation property, we develop a method that can uniformly coat a thin layer of silver on the Cu NWs through a galvanic replacement reaction. The microstructure of Cu NWs and silver shell have been examined by transmission electron microscopy (TEM). The evolution of electrical resistivity for single Cu-Ag NWs was measured as a function of time by a four-point probe method. A transfer printing approach was used to fabricate the TCFs with Cu-Ag NWs. The pressure applied for the transfer printing process has been optimized to obtain a TCF with RS = 41 Ω/sq and T = 88.9 %, which gives a good figure of merit (FOM) up to 70. The Cu-Ag NWs film has demonstrated good anti-oxidation ability after thermal aging at 85 °C for 300 hours. Meanwhile, the sheet resistance of Cu-Ag NWs film remained unchanged after 1000 bending cycles, which shows the film has excellent flexibility. In summary, the Cu-Ag core-shell NWs show the good chemical stability that are able to improve the performance and reliability of the Cu NWs-based TCFs.

目錄
摘要 II
Abstract III
誌謝 V
圖目錄 IX
表目錄 XIII
第一章、緒論 1
1.1研究背景 1
1.2研究動機 2
第二章、文獻回顧 3
2.1 陽極氧化鋁模板輔助電鍍製程 3
2.1.1 多孔性模板輔助奈米線電鍍製程 3
2.1.2 陽極氧化鋁模板結構與表面形貌 4
2.1.3 陽極氧化鋁模板生成機制 5
2.1.4 陽極氧化處理參數對模板之影響 7
2.2銅奈米線製程、結構與特性 9
2.2.1銅奈米線製備 9
2.2.2奈米雙晶結構銅奈米線 14
2.2.3銅基核殼結構奈米線 16
2.2.4銅銀伽凡尼置換反應 19
2.3 奈米線透明導電薄膜 21
2.3.1透明導電薄膜發展與變遷 21
2.3.2透明導電薄膜製程 23
2.3.3透明導電薄膜光學與導電特性 25
第三章、實驗流程 28
3.1實驗設計與流程 28
3.1.1陽極氧化鋁模板製備 28
3.1.2雙晶結構銅奈米線製備 30
3.1.3銅銀核殼結構奈米線製備 31
3.1.4金屬奈米線透明導電薄膜製備 32
3.2金屬奈米線及透明導電薄膜之微結構與特性量測分析 33
3.2.1 X光結晶繞射 (XRD) 分析 33
3.2.2掃描式電子顯微鏡 (SEM) 分析 33
3.2.3穿透式電子顯微鏡 (TEM) 分析 34
3.2.4紫外光-可見光 (UV-Visible) 光譜儀分析 34
3.2.5金屬奈米線電性分析 34
3.2.6透明導電薄膜特性分析 35
3.3實驗設備與儀器 36
第四章、結果與討論 37
4.1銅奈米線電鍍製程與結構分析 37
4.2銅銀核殼結構奈米線之製備與特性量測分析 40
4.2.1 銅銀核殼結構奈米線製程 40
4.2.2銅銀核殼層結構奈米線之化學特性分析 42
4.2.3銅銀核殼層奈米線電性量測 44
4.2.4銅銀核殼層奈米線微結構分析 47
4.2.5銅銀核殼層奈米線之銀置換反應機制 54
4.3透明導電薄膜特性分析 56
4.3.1 奈米線抽濾轉印之製程 56
4.3.2薄膜透光度與導電度量測分析 58
4.3.3透明導電薄膜之氧化特性分析 60
4.3.4透明導電薄膜之機械特性分析 61
第五章、結論 62
參考文獻 63

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