近十年來貴金屬奈米線因優異的導電、導熱性而有大量的相關研究。其中銅奈米線具有最低成本的優點，可作為連接奈米積體電路或透明導電膜之導電材料。但隨著元件尺寸的微縮，銅導線所承受的電流密度增加，可能因電遷移現象而造成元件損壞。有研究指出在電鍍銅中引入雙晶結構，可大幅提升其機械強度同時減緩電遷移的效應，但如何在複雜的電鍍製程中準確控制銅奈米線的成長方向及微結構，便是本研究所要探討的問題。本研究以自製的多孔性陽極氧化鋁模板搭配低溫脈衝電鍍來製備銅奈米線，並且於製程中控制多孔性模板的厚度與孔徑大小，探討模板形貌效應對於銅奈米線成長方向及微結構之影響，並進行銅奈米線電性量測分析。實驗結果指出，在厚度約40 μm的模板下，銅奈米線會隨著模板孔徑增加，晶體成長由<111>優選方向，變成無優選方向，最後則轉為<220>優選方向，TEM的觀察下，電鍍銅奈米線的微結構初始皆為多晶結構， 具<111>優選方向的銅奈米線，在中間階段產生<111>方向單晶且內部含有緻密雙晶，成長後期則轉為<220>方向成長；無優選方向的銅線中後期呈現兩至三個晶粒互相競爭的結果；<220>優選方向的銅線中後期以<220>方向成長，並有部分雙晶晶面存在。在厚度約50 μm的AAO模板中，所沉積之銅奈米線呈現高(111)面優選方向且不會受孔徑大小的影響，此類奈米線在中後期皆為<111>方向單晶且具有緻密雙晶結構，電性分析結果亦顯示其可承受高達108 A/cm2的崩潰電流密度，同時維持合理的電阻率。

　　Noble metal nanowires have received great attention during past decade because of their spectacular electrical and thermal properties. Among them, copper nanowires (Cu NWs) is a popular interconnect material in integrated-circuit devices and transparent conducting film applications due to their cost advantage. With continuous scaling down of integrated-circuit devices, the increasing current density may lead to electromigration-induced device failure. It has been reported that the mechanical strength and electromigraton resistance of copper metallization can be greatly enhanced by introducing nanoscale twinning structure. However, how to control the growth orientation and microstructure in complicated electrodeposition process is a critical issue. In this study, Cu NWs were deposited in homemade porous anodic aluminum oxide (AAO) membrane by pulsed electrodeposition at low temperature. By controlling pore size and thickness of AAO membrane, we can synthesis Cu NWs with different crystallographic orientation and twinning structures. The growth orientation of Cu NWs change from <111> to mixed mode and to <220> with increasing pore size in thin AAO template. The corresponding microstructure changed from partially nanotwinning to polycrystalline and single crystal eventually. Surprisingly, the Cu NWs shows strong (111) preferred orientation when deposited in thicker AAO template in spite of different pore size. The Cu NWs show continuous and large portion nanotwinned structure which can sustain high failure current density up to 108 A/cm2 also remains reasonable electrical resistivity.

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