臺灣博碩士論文加值系統

本實驗以無電鍍銅技術，在晶片表面進行鍍上一層導電用的銅膜。結果發現將TiN/SiO2/Si晶片，先經敏化活化之後，以傳統無電鍍銅鍍浴加以調整成的TiN鍍浴，在60C浴溫、50 rpm轉速下進行無電鍍，可以得到平整、連續且附著力良好的銅膜。Cu鍍浴在50C浴溫、50 rpm轉速下，亦可在活化之Cu/TaN/SiO2/Si晶片鍍上一層優良銅膜；但是在Cu/Ta/SiO2/Si晶片上所鍍的銅膜附著不良。隨著銅膜厚度的增加，銅膜表面的凹凸粗糙度會增加；在1 m厚度時，凹凸的平均高度為54.9 m，均方根粗糙度為14.7 m。X-光繞射分析得知，400C、60 min的退火處理，可以降低銅膜內部缺陷與提高銅膜優選方位的程度；所以退火處理可以將銅膜原來的2.1~4.5 -cm電阻率降為1.75 -cm，相當接近銅塊材的1.67 -cm。由有挖洞的Cu/TaN/SiO2/Si晶片無電鍍銅膜的結果可知，無電鍍銅膜的階梯覆蓋能力及填洞能力相當好；可沿著各種凹凸表面覆蓋一層均勻的銅膜；也可填滿直徑0.2 μm、深寬比5：1的洞。顯示無電鍍銅技術在積體電路的薄膜導線應用上，具有相當高的潛力。

誌謝
摘要…………………………………………………………………….……i
目錄…………………………………………………………………………ii
圖目錄……………………………………………………………………....v
表目錄…………………………………………………………………….viii
壹、前言……………………………………………………………………1
貳、文獻回顧………………………………………………………………2
2.1.超大型積體電路(Ultra Large Scale Integration Circuit)之內連線(Interconnect)簡介………………………………………………….….2
2.1.1. 金屬內連線之用途……………………………………………..2
2.1.2. 常用金屬內連線之材料與製造方法………………………..…2
2.1.3. 以銅取代鋁的原因……………………………………………..5
2.1.4. 銅金屬製程……………………………………………………..5
2.2 無電鍍銅簡介…………………………………………………………..7
2.2.1. 無電鍍(Electroless Plating)…………………………………….7
2.2.2. 無電鍍銅製程發展簡介………………………………………..7
2.3. 無電鍍製程之前處理…..……………………………………………...8
2.4. 無電鍍銅鍍浴的組成與特性……………………...…………………10
2.4.1. 銅鹽……………………………………………………………11
2.4.2. 還原劑…………………………………………………………11
2.4.3. 錯化劑…………………………………………………………13
2.4.4. 安定劑…………………………………………………………15
2.4.5. pH調整劑……………………………………………………....16
2.5. 無電鍍銅的化學反應式與反應機構………………………………...16
2.5.1. 化學反應式[12]………………………………………………..16
2.5.2. 反應機制[31]………………………………………………….17
2.6. 近年來無電鍍銅在積體電路製程應用上之發展…………………...18
2.7. 研究目的……………………………………………………………...20
參、實驗步驟………………………………………………………………24
3.1. 基材…………………………………………………………………...24
3.2. 基材之前處理………………………………………………………...24
3.2.1.清洗……………………………………………………………..24
3.2.2.敏化處理………………………………………………………..24
3.2.3.活化處理………………………………………………………..26
3.3.無電鍍銅鍍浴組成…………………………………………………….26
3.4. 無電鍍銅設備………………………………………………………...26
3.5. 實驗流程簡介………………………………………………………...27
3.6 熱處理………………………………………………………………....27
3.7. 無電鍍銅膜微結構觀察及性質分析………………………………...27
3.7.1. 掃描式電子顯微鏡(SEM)分析………….……………………32
3.7.2. X-ray繞射分析………………………………………………...32
3.7.3. 電阻率量測……………………………………………………32
3.7.4. 原子力顯微鏡(AFM)………………………………………….34
3.7.5. 附著力測試……………………………………………………34
肆、結果與討論……………………………………………………….…..35
4.1. 無電鍍銅膜在TiN上的情形…………………………………….…..35
4.1.1 無電鍍參數與鍍浴成份……………………………………….35
4.1.2. 退火處理………………………………………………………45
4.2. 無電鍍銅膜在銅晶種層上的情形…………………………………...56
4.2.1. 在CS銅晶種層上的情形……………………………………..60
4.2.2. 在TT銅晶種層上的情形……………………………………..62
4.3. 無電鍍銅膜在有圖案TT銅晶種層上的情形………………………80
4.4. 附著力測試…………………………………………………….. ……84
伍、結論……………………………………………………………………94
陸、參考文獻………………………………………………………………95

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