隨著電子產品不斷朝著輕薄短小的方向發展，早期積體電路片（chip，又稱為晶片）內部導線所使用的鋁材已不敷使用，由於鋁材料尺寸小於1μm時，它的RC值將會明顯增加，使得更小尺寸的晶片之效能與發展受制於內部導線。銅導線製程因此被開發出來，取代了原先的鋁導線。甚至研發出多層次晶片的製程，使得小尺寸晶片的效能大幅提昇。而多層次晶片之間如果能直接以銅導線做為支撐，則不會有散熱不易以及增加多餘重量與成本的問題。
　　但是銅與其他高導電金屬同樣有著強度過低的問題。雖然有許多強化機制（strengthening mechanisms）可以提高金屬的強度，但同時卻也大幅增加對電子的散射，而使導電率降低。然而利用脈衝電鍍法（Pulse Electrodeposition）可以製備出有高密度奈米雙晶（twin）的純銅試片，同時具有超高強度和高導電性。
　　本實驗固定脈衝電鍍的脈衝頻率，改變電流密度，再利用背向電子散射繞射（Electron Back-Scatter Diffraction，EBSD）和XRD分析，觀察以不同電流密度所製備出的銅鍍層，比較各試片之間的晶粒尺寸與雙晶密度。實驗中並成功以EBSD分析未經研磨拋光處理的銅鍍層表面形貌（morphology）的OIM（Orientation Image Mapping），以及從橫截面觀察銅鍍層的晶粒形狀與晶體方向。另外發現電流密度的增加並沒有如預期中地讓鍍層表面的平均晶粒尺寸變小；電流密度的增加也沒有對雙晶的生成有規律性的影響。而鍍層的優選方位在鍍層表面有集中於(111)及(101)方向的趨勢。橫截面的晶粒形狀與晶體方向，大多都是朝著幾個方向成長的大型柱狀晶。

　The performance of aluminum interconnection in chips was not enough because of those electronics products getting thinner and smaller. The efficiency and development will be limited through interconnections. when the size of aluminum inter connects are smaller than 1μm, its RC value will increase obviously. Copper interconnect was developed for replacing aluminum. To raise the performance of small chip, multi-layer chips process has been developed. The problems of heat dissapitation, weight and cost addition will be solved if multi-level chips could use copper wires to support one another directly.
　Like other high conductivity metals, the strength is not enough in copper’s composition. Even strengthening mechanisms can increase the strength of metal, it will violently increase electron scatter causing the poor conductivity. Using pulse electrodepositions can produce high nanometer twin pure copper samples which comprise high strength and high conductivity.
　In this study, we modified the current density of PED, analyzed samples by EBSD and XRD, then observed the film of copper samples which prepared through different current densities, and compared each sample’s grain size and twin density. In addition, this study successfully analyzed unpolished morphology OIM of the film of copper by EBSD, and observed the grain shape and orientation of the cross- sectional in copper films. Increasing the current density didn’t make the grain size in the surface of film become small like we have expected. Moreover, it didn’t make have any influences in common of twin density. The orientation on film surface concentrated toward direction 111 and 101. Most of grain size and orientation of cross-section developed huge columnar grains toward some specific directions.

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