臺灣博碩士論文加值系統

隨著超大積體電路(ULSI)製程的發展、多層金屬連接電路技術的複雜，對於每層表面的平坦化要求將更加嚴苛。為了增加導線的電傳導能力及阻抗電子遷移的能力，目前有使用銅材來代替鋁材的趨勢。 但是銅的機械性質較鋁材為軟，所以在化學機械拋光的加工過程中，在導線上產生碟狀缺陷的現象更加明顯。 如何藉由控制化學機械拋光的加工參數以減少碟狀缺陷的現象，是我們的研究目標。
在本論文中，認為碟型缺陷是由於兩種材料的移除率所造成，首先，根據王氏模型來建立熱氧化層跟金屬銅層的移除率模型，再利用兩種不同材料的移除率來預測碟型缺陷的深度。並考慮線寬、圖型密度、施加壓力與研磨墊剛性等因素對碟型缺陷深度的影響，根據這些結果來進行討論跟探討，以便讓我更了解碟型缺陷的機制。
論文最後將碟型缺陷的實驗量測值與模擬結果進行比對，並與兩位學者所提出的碟型缺陷深度的模型進行比較，比較結果顯示利用移除率所發展的模型較能接近實際量測的深度，利用所提出的模擬方法可得到較少的誤差。

The objective of this study was to establish an approach to simulate and predict the behavior of dishing. The dishing phenomenon was an key issue for the chemical mechanical planarization of wafer, especially when copper was used as the conducting material. It was believed that the dishing phenomenon was due to the selectivity of chemical erosion effect and the distribution of pressure will determine the final profile of the dishing. The established model required preliminary experiments to determine the material removal rate. Verification experiments will also be conducted to evaluate the proposed approach

Contents………………………………………………………………….I
Figure and Table Captions………………………………………………III
Chapter One Introduction……………………………………………...1
Chapter Two Literature Survey………………………………………..5
2.1 Polishing mechanism in the CMP process……………………….5
2.2 Dishing phenomenon in patterning wafers……………………….8
2.3 CMP models……………………………………………………..11
2.4 Summary………………………………………………………...19
Chapter Three Dishing Simulation Approach and Material Removal Tests………………………………………………….22
3.1 Approach to simulate dishing behavior……………………….…22
3.2 Material removal tests for copper and SiO2……………………..23
3.3 Test results and material removal models………………………..26
Chapter Four Simulation Study of Dishing Behavior and Material Removal………………………………………………41
4.1 Effects of process parameters on material removal……………..41
4.2 Effects of process parameters on dishing behavior……………..43
Chapter Five Verications Experiments………………………………62
5.1 Experimental design and setup for verification tests……………62
5.2 Results and discussions………………………………………….63
Chapter Six Comnclusions and recommendations…………………..78
6.1 Conclusions…………………………………………………….78
6.2 Recommendations for future research………………………….79
Reference……………………………………………………………….82

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