在電子元件製程中，填入銅金屬導線的主要方式為電鍍法。然而，複雜的元件結構使金屬導線存在應力集中的問題，進而導致元件失效。為改善此問題，具有高機械強度以及良好導電性的奈米雙晶銅結構，成為近年來被廣泛研究的主題。奈米雙晶銅常見的製備方式是脈衝電鍍法，可藉由電鍍製程參數調控雙晶間距，但其具有低鍍率的缺點。因此如何透過電鍍製程參數的調控，在銅導線中有效導入奈米雙晶結構，是一個值得研究的課題。本研究使用直流電鍍法製備銅薄膜，探討超音波震盪製程和電鍍液中的酒石酸添加劑對電鍍銅鍍膜微結構及其機械性質的影響。透過掃瞄式電子顯微鏡及聚焦離子束系統分別觀測銅薄膜的表面形貌及橫截面影像，發現超音波震盪製程或是添加酒石酸在電鍍液中皆使薄膜中晶粒尺寸有增大的趨勢。X光結晶繞射實驗結果則顯示銅薄膜擁有較高的(111)晶面優選方向，此外奈米雙晶結構傾向在較厚鍍膜中生成。此奈米雙晶結構可有效提升銅電鍍膜層之硬度。根據實驗結果推論超音波震盪處理可以降低電鍍過程中離子擴散層的厚度，促進還原電極表面的原子表面擴散速度，降低過電位(overpotential)，增加原子層狀成長的機會; 而電鍍液添加劑則會吸附在還原電極表面，減少成核位置與數目。根據微結構觀察及奈米壓痕測試結果顯示超音波震盪製程和電鍍液添加劑將增加電鍍銅膜生成奈米雙晶的機率及薄膜的機械硬度。

Electroplating is a main-stream process used to fill the metal layer of integrated circuits. However, owing to the complication of the circuit structure, the metal layer may suffer local stress concentration, leading to device failure. Nanotwinned Cu that has high mechanical strength and good electrical conductivity is considered as an excellent interconnect material. By using the pulse-current deposition method, we are able to introduce a nanotwinning structure in Cu metallization with various twin spacing. Nonetheless, the pulse-current electrodeposition has a lower deposition rate than the direct-current one, which may not be the promising solution for industrial fabrication process in terms of run rate and cost considerations. In this study, we intend to investigate the effects of ultrasonic agitation and electrolyte additives on microstructure and mechanical property of Cu films prepared by direct-current electroplating method. Both the ultrasonic agitation and specific electrolyte additive can enhance average grain size of the electroplated Cu films according to the images obtained by scanning electron microscopy and focused ion beam system. The x-ray diffraction results show that the Cu films prepared with ultrasonic agitation and electrolyte additive have enhanced (111)-oriented film texture. In an electroplating process with ultrasonic agitation, a two-dimensional layer growth mechanism prevails owing to the reduced diffusion layer thickness and overpotential together with the enhanced surface diffusion of Cu adatoms. The function of electrolyte additive adsorbed on the cathode surface may decrease the available nucleation sites and enhance the two-dimensional growth as well. Based on the microstructure inspection and nano-indentation measurements, ultrasonic agitation and appropriate electrolyte additive can raise the possibility of forming dense nanotwinning structure and increase the hardness of electroplated Cu films.

目錄
誌謝 I
摘要 II
Abstract III
目錄 IV
圖目錄 VI
表目錄 IX
第一章、緒論 1
1.1 背景簡介 1
1.2 研究動機 2
第二章、文獻回顧 3
2.1奈米雙晶電鍍銅膜之製程與生成機制 3
2.2超音波震盪攪拌電鍍製程 6
2.2.1超音波對溶液環境擾動之原理及特性 7
2.2.2超音波震盪攪拌對電鍍製程電化學特性之影響 10
2.2.3超音波震盪攪拌對電鍍鍍膜性質之影響 13
2.3添加劑對電鍍膜性質影響 14
第三章、實驗步驟 18
3.1電鍍種子層製備 18
3.1.1電子束蒸鍍種子層 18
3.1.2磁控濺鍍種子層 20
3.2電鍍製程條件 21
3.3銅膜微結構與性質分析 23
3.3.1 α-step 薄膜厚度輪廓 2
3.3.2 X光繞射分析儀 23
3.3.3 FE-SEM 冷場發射掃描式電子顯微鏡 23
3.3.4 FIB離子束聚焦顯微鏡 23
3.3.5奈米壓痕儀 24
第四章、結果與討論 25
4.1電鍍製程參數對電鍍銅膜微結構與性質之影響 25
4.1.1鍍膜表面形貌、橫截面微結構及晶粒尺寸 25
4.1.2鍍膜成長方向 29
4.1.3鍍膜雙晶結構與機械性質 30
4.2電鍍銅膜成長機制探討 32
4.2.1超音波擾動與酒石酸添加對鍍膜晶粒尺寸變化 32
4.2.2超音波擾動與酒石酸添加對鍍膜成長方向變化 36
4.2.3超音波擾動與酒石酸添加對鍍膜雙晶結構生成之影響 41
第五章、結論與未來發展 45
5.1結論 45
5.2未來發展 45

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