摘 要
化學機械拋光為半導體製程中最常用的平坦化製程，本文探討銅膜CMP拋光過程既有應力與外加應力對拋光製程材料移除之影響。前者為晶圓薄膜濺鍍過程所殘留之應力，後者為CMP拋光製程中所之施加應力。
本文以純腐蝕、純機械拋光及CMP拋光三組實驗進行分析。研究主要發現（1）沈積薄膜與退火後之薄膜均為張應力，張應力將使金屬鍵結受拉伸，進而促使腐蝕率增加。（2）退火後薄膜應力均增加，厚度為1,000nm與2,000nm銅膜之退火溫度愈高應力愈大；而厚度為1,500nm銅膜之退火溫度愈高應力反而下降。以相同退火溫度之實驗結果顯示，退火溫度為150°C及250°C時，薄膜應力愈大，導致較大的移除率。而退火溫度為200°C之銅膜，雖然應力愈大但移除率並沒有增加反而下降。（3）厚度為1,000nm銅膜之退火溫度愈高則應力愈大，對應的腐蝕速率也愈大。（4）以厚度1,000nm銅膜進行連續拋光，並量測其應力與厚度，結果顯示，當銅膜厚度低於450nm以下時，移除率明顯增加，當厚度低於此值時，既有應力將強烈影響移除率。（5）實驗顯示純機械拋光移除率甚低，其值小於20Å/min，顯示化學機械拋光之效應並非單純機械效應與化學效應之線性合成。

ABSTRACT
Chemical mechanical polishing (CMP) is the most commonly used process in the planarization of wafer surfaces. This thesis, from the stress viewpoint, investigates the effects of intrinsic stress and extrinsic stress on the removal rate of copper CMP. The former is the stress from the sputtering and annealing processes while the latter is the stress occurred in the polishing process.
Three types of experiments are designed and conducted in this thesis, including chemical corrosion, mechanical polishing, and CMP. Achievement of this study includes the following items: (1) The copper film after sputtering and annealing sustains tensile stress that intensifies corrosion rate. (2) Film stress increases after annealing. For copper film with 1,000 nm and 2,000 nm in thickness, the stress increases as the annealing temperature increases. For film of 1,500nm in thickness, the stress decreases with the annealing temperature. The corrosion rates of films with annealing temperature at 150°C and 250°C increase with film stress. But the rate decrease with film stress for copper film annealed at 200°C. (3) The stress of 1,000nm thick copper film increases at high annealing temperature. Meanwhile, the corresponding corrosion rate increases. (4) Continuous polishing on 1,000nm copper film showed that the removal rate increases rapidly. The removal rate is strongly dependent upon film stress under this condition. (5) The removal rate of mechanical polishing, however, is relatively low. As the rate is less than 20Å/min, it indicates that the removal mechanism of CMP is not a simple superposition of chemical corrosion and mechanical polishing.

目 錄
摘要 Ⅰ
英文摘要 Ⅱ
致謝 Ⅲ
目錄 Ⅳ
圖目錄 Ⅶ
表目錄 Ⅹ
符號說明 XI
第一章 緒論 1
1.1前言 1
1.2 研究目標 2
1.3 文獻回顧 3
1.3.1 應力強化腐蝕效應 3
1.3.2 製程溫度之效應 4
1.3.3 化學機械拋光文獻回顧 5
1.4 研究方法與步驟 12
1.5 本文大綱 12
第二章 應力強化腐蝕機制 13
2.1 金屬腐蝕原理 13
2.1.1 電極反應 13
2.1.2 腐蝕生成物及鈍化性 15
2.2腐蝕與機械雙重作用 16
2.2.1 沖蝕耗腐蝕 16
2.2.2 腐蝕性磨耗 20
2.2.3 應力腐蝕破裂 21
第三章 應力分析 24
3.1 既有應力 24
3.1.1熱應力分析 25
3.1.2應力釋放 26
3.2薄膜應力量測 29
第四章 實驗規劃 32
4.1 既有應力與外加應力之實驗設計 33
4.1.1既有應力之實驗設計 33
4.1.2外加應力之設計 34
4.2細部實驗流程規劃 36
4.2.1前導實驗之規劃 36
4.2.2既有應力實驗流程 36
4.2.3 外加應力實驗流程 39
4.3 實驗設備 40
第五章 實驗結果與分析 42
5.1 前導實驗結果分析 43
5.1.1純化學腐蝕結果 43
5.1.2薄膜應力分析 44
5.1.3銅膜阻值量測分析 45
5.1.4純化學腐蝕實驗分析 46
5.2既有應力與純機械拋光總和應力效應分析 54
5.2.1既有應力與純機械拋光總和應力實驗結果 55
5.2.2銅膜阻值量測分析 55
5.2.3 純機械拋光與移除率分析 56
5.3既有應力與化學機械拋光總和應力效應分析 59
5.3.1既有應力與外加應力分析 59
5.3.2厚度與應力分析 62
5.3.3應力與移除率之結果分析 65
5.4既有應力與外加應力綜合性分析 70
5.4.1退火前後應力分析 70
5.4.2移除率與表面粗度分析 72
5.4.3應力與移除率分析 72
第六章 結論與未來展望實 77
6.1 結論 77
6.2 未來展望 78
參考文獻 80
附錄A Tencor TLX-2320 Thin Film Stress Measurement規格 86
作者簡介 88

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