在現今半導體晶片製程中，為了增加效能採用多層的電路設計，使得各層電路之平坦化製程相對重要，因此在半導體製程中化學機械平坦化(Chemical-Mechanical Planarization, CMP)逐漸占有重要的地位。在CMP中，拋光液(Slurry) 佔了整體製程成本之一大部分。因此本研究建構一套流場可視化(Flow visualization, FV)設置，透過紫外光誘導螢光(UV-excitation fluorescence method, UVEF)之方法，觀察傾斜式拋光液注入化學機械拋光系統之拋光液流動行為與各參數之影響。將光學設置的鏡頭放大倍率分成0.5倍以及2倍設置並加上配重機制，可調整下壓力範圍為0.27~1.5psi。而藉由攝影機記錄拋光液之流場，可利用影像處理將相對濃度量化並得其分佈，並對於傾斜式注入角度與各機台參數之關係以及搭配不同拋光墊設計進行探討。觀測結果顯示，放大倍率為0.5倍設置在同心圓拋光墊上，測得拋光液進入晶圓後穩定時間約為20秒，而定義出拋光液在晶圓區域之均勻性以及平均濃度值兩個關鍵指標判斷實驗參數之優劣依據。兩種設置量測出向外注入傾斜角度為60°使拋光液進入晶圓中較均勻以及濃度較高，而在各自下壓力範圍中最大下壓力較為均勻。在放大倍率2倍設置下，觀察實驗參數變化在不同拋光墊溝槽圖案上之拋光液散佈變異，以同心圓拋光墊利用向外注入角度為60°搭配最高轉速70rpm和最大下壓力1psi均勻性指標以及濃度值分別為0.05、0.24，在均勻性指標中差異在整體上最小，較XY型拋光墊在相同參數中整體表現上較佳，代表其有助於拋光液濃度分佈進入晶圓區域之均勻性。

In modern semiconductor fabrication process, it is important to achieve very high levels of planarity of the interfaces between copper and oxide insulating layers for the IC performances keep improving. Therefore, CMP (Chemical-Mechanical Planarization) process gradually becomes one of the key process for semiconductor manufacturing. Slurry flow is one of the crucial component in CMP process. However, the slurry consumption is a part of the operation cost and limited efficiency during CMP process. In this study, an experimental setup of flow visualization of the slurry flow in a Chemical Mechanical Planarization (CMP) system was constructed. By using UV-excitation fluorescence method(UVEF), the behavior of slurry flow injected by an inclined jet and process parameters were investigated. Two optical configurations was set to produce the magnification of 0.5X and 2X. By adding a counterweight mechanism, the downforce of the CMP process can be set to a range from 0.27 to 1.5psi. Through the images and data post-processing, the distribution of relative concentration was obtained and compared. The differences in the slurry concentration distribution were investigated with inclined angles of the injector, the parameter of polishing machine and different polishing pad patterns. The 0.5X magnification results show that in the concentric polishing pad case, the stable time is measured to be about 20 seconds. The uniformity and average concentration under the wafer are defined as the major performance indices for evaluating performances of the setting of parameters. With both two optical setups higher concentration and more uniform distribution are reported with outward slurry injection angle is set to 60° and under the maximum down force setting. The lens magnification of 2X setup is used to observe the slurry distribution under the wafer with different polishing pad patterns. In concentric pattern case with outward injection angle 60°, rotating speed of 70rpm, and down force of 1psi, the uniformity and the average concentration value are 0.05 and 0.24, respectively. It has the best uniformity among all cases, which means this parameter set may distribute slurry flow under wafer more uniformly. Overall, the performance of the concentric polishing pad pattern is better than the XY type polishing pad pattern.

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