本研究透過交錯式電極最佳化設計，以優化電致動力輔助化學機械平坦化製程(Electro-Kinetic Force Chemical Mechanical Planarization, EKF-CMP)，應用於銅膜晶圓(CuB)、奈米雙晶銅膜晶圓(Nanotwinned-Copper, Nt-Cu wafer)、奈米雙晶銅圖案化晶圓(Nanotwinned-Copper /Polyimide, Nt-Cu/PI pattern wafer)。本研究目標為達到Nt-Cu/PI中銅柱(Bump)形貌高於Polyimide(PI)之階梯形貌，並改善Bump以及PI之導線凹陷(Dishing)問題。本研究使用COMSOL Multiphysics商用模擬軟體建構電滲流模組，利用頂層粒子濃度指標進行模擬數據量化，靜態模擬結果顯示電極寬度以及間距為2 mm具最濃頂層粒子濃度；移動式電滲流模組模擬以靜態最佳化電極設計進行平行式移動電極模擬，模擬結果顯示EKF-CMP在相同速度下可提升頂層粒子濃度。本研究使用實驗設計方法進行CuB與Nt-Cu製程分析，由趨勢圖得知影響材料移除率(Material Removal Rate, MRR)最大者為拋光液流率。以最佳化參數進行Nt-Cu/PI平坦化製程，實驗結果驗證EKF-CMP之製程時間可縮短20%，Nt-Cu與PI之Dishing改善率分別為16.35%以及3.31%。本研究結果可改善奈米雙晶銅圖案化晶圓製程應用。

In this study, the optimized electrode design enhances the Electro-Kinetic Chemical Mechanical Planarization (EKF-CMP) process. This research studies several types of wafers such as Copper blanket wafer (CuB), Nanotwinned-copper blanket wafer (Nt-Cu wafer), and Nanotwinned Copper/Polyimide pattern wafer (Nt-Cu/PI pattern wafer). The goal of this research is to obtain a step-height profile of the Nt-Cu/PI wafer by CMP. As the Nt-Cu profile is higher than Polyimide (PI), it further reduces dishing problem of the bump and PI. The COMSOL Multiphysics commercial simulation software is used to construct electro-osmosis flow (EOF) simulation modules. Simulation analysis uses particle concentration on the top layer of the liquid layer, between the wafer and pad, as an index for the simulation. The moving EOF model uses the optimized static electrode design as a basis voltage for parallel moving electrode simulation. The simulation results show that EKF-CMP increases the particle concentration of the top layer at a similar velocity. As a result, the effect of polishing platen speed in EKF-CMP is greater than EOF. The experiment is completed with the planarization process of CuB and Nt-Cu by Design of Experiment (DOE) method. The slurry flow rate exhibits a significant impact on the Material Removal Rate (MRR) of CMP. The planarization process of Nt-Cu/PI pattern wafers conducts with the optimized parameters and results show that the EKF-CMP process shortens the processing time by 20%, and the dishing effects of Nt-Cu and PI can reduce by 16.35% and 3.31%, respectively. Results of this study can be used to improve Nt-Cu/PI pattern wafers for wafer fabrication applications.

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