臺灣博碩士論文加值系統

　　遵循著摩爾定律下，積體電路不斷的縮小下，在次微米製程中導線線寬在180奈米下時，已經由銅線取代原本所使用的鋁線做為金屬連接材料，然而為了防止銅在製程或者使用期間與矽基板間相互擴散導致元件退化，在銅與矽基材之間沉積出一層厚度均勻且具有高熱穩定性以及良好的界面附著性的擴散阻障層，本實驗利用金屬鋅具有較大的擴散係數以及在升溫時易與二氧化矽產生反應，因為在高溫時擁有較大的驅動力下能與二氧化矽相互作用，自行形成擴散阻障層，以防止銅與矽之間的互相擴散反應。
　　本研究利用非水溶液來進行銅鋅薄膜的脈衝電鍍，此非水溶液為深共晶溶液，將銅鋅薄膜沉積於白金基板以及銅基板上，並在真空下進行銅鋅薄膜的熱處理，以觀察金屬鋅與二氧化矽層反應，形成擴散阻障層，銅鋅薄膜以掃描式電子顯微鏡(SEM)觀察銅鋅薄膜的表面以及橫截面，能量散佈光譜儀(EDS)進行銅鋅薄膜的定量及定性分析，X-ray繞射儀(XRD) 進行薄膜中相的分析，.歐傑電子能譜儀(AES)及X射線吸收光譜(XAS)分析薄膜價態以及縱深分析，接下來利用交流阻抗分析(EIS)、循環伏安法(CV)等電化學分析深共晶溶液之電解液的特性以及Hall effect 跟四點探針量測薄膜之電性值。
　　本研究結果顯示，利用深共晶溶液當為電解質時在經過12小時後仍然具備著良好的導電性，以及在電解液中銅鋅濃度比例為1:1(Cu:0.006M，Zn:0.006M)，電流密度為1.5mA/cm2電鍍時間為30分鐘，可以得到均勻且平坦的薄膜，經由結構分析過後確定為銅、鋅以及氧化心所組成。銅鋅薄膜在400下熱處理1小時後，薄膜中的鋅順利擴散至二氧化矽層，且銅的部分並未變成銅矽化合物，故成功的在深共晶溶液中製備出擴散阻障層。

According to the Moore’s law, the feature size of integrated circuit is constantly shrink down. When the line width of aluminum was shrink down to 180nm, it has problem of high resistance, severe RC delay and electromigration effect. The aluminum wire was replaced by copper wire, because the copper wire has a better electric conductivity to improve the above problem. In order to prevent Cu fast diffusion into the silicon layer and the performance of device degradation, a robust diffusion barrier is strongly required. The good diffusion barrier should meet some certain criteria such as uniform thickness, high thermal stability and good adhesion between Cu interconnect and the silicon layer. In the study, Zinc is chosen as the material for self-forming diffusion barrier due to its highly reactive with the silicon layer under elevated temperature. The Cu-Zn alloy film followed by thermal annealing, Zn diffuse to the silicon layer and the Zn-silicate is formed at the interface between Cu interconnect and silicon layer.
　　
　　In the work, a non-aqueous solution that deep eutectic solvent, were used for the deposition bath. Pulse-current deposition was applied for the co-deposition of copper-zinc film on the Pt wafers and Cu wafers.

摘要 i
致謝 v
圖目錄 viii
表目錄 x
一、 前言 1
二、 文獻回顧 3
2.1、擴散阻障層 3
2.1.1、擴散阻障層的機制 3
2.1.2、擴散阻障層的選擇與製備 6
2.1.2.1、擴散阻障層的選擇 6
2.1.2.2、擴散阻障層的製備 8
2.1.3、選擇銅鋅合金的原因 10
2.2、非水溶液電解質 14
2.2.1、離子液體 14
2.2.2、深共晶溶液 16
三、 實驗步驟 21
3.1、實驗設計 21
3.1.1、實驗流程 21
3.1.2、實驗配置 23
3.1.3、實驗藥品與基材 25
3.1.4、實驗儀器 27
3.2、薄膜的特性分析 28
3.2.1、掃描式電子顯微鏡(Scanning Electron Microscope, SEM)、能量散射光譜儀(Energy-Dispersive X-ray Spectroscopy, EDS) 28
3.2.2、X-ray 繞射儀（XRD, X-ray diffraction） 29
3.2.3、歐傑電子能譜儀分析(Auger electron spectrometer, AES) 30
3.2.4、四點探針（Four Point Probe） 30
3.3、電解液性質分析 31
3.3.1、電化學阻抗頻譜法(Electrochemical Impedance Spectroscopy, EIS) 31
3.3.2、循環伏安法(Cyclic Voltammetry, CV) 33
四、 結果與討論 35
4.1、深共晶溶液製備銅鋅合金薄膜 35
4.1.1、不同製備條件對銅鋅合金薄膜的影響 35
4.1.1.1、改變電解液之銅鋅濃度與電鍍之電流密度 35
4.1.1.2、銅鋅薄膜成分組成 48
4.1.2、電解液的電化學分析 49
4.1.2.1、交流阻抗分析 49
4.1.2.2、循環伏安法 53
4.1.3、熱處理對銅鋅合金薄膜的影響 55
4.1.3.1、真空熱處理 55
五、 結論 63
六、 參考文獻 64

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