在電子元件的製程中，金屬導線的填入主要是利用電鍍的方式。除了傳統的直流電鍍外，脈衝電鍍也被廣泛的應用在不同的製備需求上。然而在電鍍的研究中，關於電鍍液溫度的探討比較缺乏，尤其在室溫以下電鍍製程的研究非常稀少。此外，具有奈米雙晶的銅金屬因具有高機械強度以及良好的導電性，在近年來被廣泛的研究，而其中一種製備方式就是採用脈衝電鍍，而銅膜內的雙晶間距與脈衝電流的電流密度以及有效時間有關，但對於溫度的影響並沒有相關的研究。故在本研究中將探討直流電鍍以及脈衝電鍍在不同溫度下的影響，並探討溫度效應對於電鍍形成雙晶的影響。
　　在本研究中發現，不論是直流電或是脈衝電流，工作電壓都會隨著溫度下降而上升，推測是因為電鍍液中的銅離子在低溫時擴散速率下降所造成。而在銅膜晶體成長方向的研究中發現，直流電鍍製程在低溫時會有明顯轉換，將從無優選方向轉成 (111) 面成長，而在脈衝電鍍中則無明顯的轉換。兩者間的差別可由銅原子在晶體表面擴散的速率以及電鍍時的過電位來解釋。而在表面形貌的部分，從SEM的觀察可發現，晶粒細化的現象在直流電中遠較脈衝電流中來的明顯，且從銅膜表面粗糙度的量測中，直流電的粗糙度會隨著溫度下降而下降，而脈衝電流則呈現相反的趨勢。主要的原因來自於成核半徑以及晶核成長方向的改變。另外在冰點以下時，由於電鍍液中的離子濃度呈現不均勻的分佈，造成工作電壓以及粗糙度都有反轉的趨勢。最後在脈衝電鍍銅膜的雙晶結構中，由TEM的結果可以發現雙晶的間距會隨著電鍍時的溫度下降而跟著縮減。而從硬度上的量測也證實此結果。推測是低溫下應力釋放的機制轉換及銅膜內應力上升的緣故。
　　本實驗中證明低溫下電鍍確實能對銅膜的微結構進行改質，不同電流模式下，對於溫度的反應也不同。而在電鍍形成雙晶過程中，可在相同的電流密度下藉由降低電鍍液溫度來對雙晶密度做調整。故在未來的研究中，電鍍液的溫度將可引入製程的可變參數中，並探討最佳化的溫度範圍。

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