銅導線因具有低製造成本、成熟製程以及優異導電率，已廣泛應用於半導體封裝產業。然而，隨著導線線寬持續縮小與電流密度提高，銅導線在通電過程中可能因電遷移效應而產生微觀結構變化，甚至出現類似傳統熱退火所造成之再結晶現象，進而影響其導電與可靠度表現。過去文獻多將此現象歸因於通電時所伴隨之電效應與熱效應，但兩者對微觀結構演變所造成的個別影響，以及通電行為與傳統熱退火再結晶之間的關聯，仍尚未被完整釐清。
本研究以脈衝電鍍銅試片作為研究對象，透過通電前後之電子背向散射繞射技術（electron backscatter diffraction, EBSD）分析，比較其晶粒取向、取向差與晶界分布之變化，以探討通電所導致之微觀結構演變行為。由於銅本身具有極低電阻率，通電過程中焦耳熱所造成之溫升遠低於銅之再結晶溫度，因此本研究可進一步降低熱效應干擾，並著重於分析電效應對銅微觀結構變化之影響。同時，本研究亦結合傳統熱退火再結晶之必要條件，進一步討論通電後所觀察到之取向偏移與取向差變化是否具有再結晶相關特徵。
研究結果顯示，通電24小時後，銅試片之不同晶面會產生不同程度的取向偏移。當晶面平行於電子流方向時，{111} 晶面表現出最高穩定性，其偏移角度最小，約為 2.65°；而當晶面垂直於電子流方向時，{111} 與 {110} 晶面則產生較明顯之角度偏移，分別為 9.36° 與 9.20°。此外，通電亦會導致試片內部應力狀態與取向差分布發生改變，其中 {110} 晶面具有最大的取向差增加量，約為 0.07°，而 {100} 晶面則呈現取向差降低之趨勢，約為 -0.04°。本研究之貢獻在於釐清通電條件下銅微觀結構變化與晶面取向之關聯，並指出電效應可能在低熱效應條件下促使晶粒取向偏移、取向差改變及局部再結晶相關行為，對於理解高電流密度下銅導線之微觀結構穩定性與可靠度具有重要參考價值。

Copper interconnects are widely used in semiconductor packaging due to their low cost, mature fabrication process, and excellent electrical conductivity. However, increasing current density in miniaturized interconnects may induce electromigration-related microstructural evolution, affecting their reliability. In this study, pulse-electrodeposited copper specimens were analyzed by electron backscatter diffraction (EBSD) before and after current stressing to investigate changes in grain orientation, misorientation, and grain boundary distribution. Since the temperature rise caused by Joule heating was far below the recrystallization temperature of copper, the influence of thermal effects was minimized, allowing the electrical effect to be examined more directly. The results show that current stressing caused orientation deviation in different crystallographic planes, with the degree of deviation depending on the relationship between crystallographic orientation and electron flow direction. Changes in misorientation distribution were also observed, suggesting variations in internal stress and local lattice distortion. These findings indicate that electrical effects may promote orientation deviation and localized recrystallization-related behavior in copper under limited thermal influence.

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