本論文研究的主要目的，係探討在銅化學機械研磨製程中，二氧化矽磨粒與金屬導線置於不同研磨液成分的條件下，材料在奈米尺度下的摩擦行為與化學反應。本研究使用分子動力學法與可模擬化學反應的ReaxFF勢能函數，並配合開放式軟體LAMMPS作為工具，分別建立當置於三種不同研磨液下，二氧化矽磨粒對銅導線在不同研磨壓力及不同磨耗速度下之奈米磨擦模擬。模擬結果顯示，當研磨液為雙氧水溶液時，化學反應生成的化合物最多，同時可以觀察到過氧化氫分子與水分子間不斷地互相結合與分離的現象。若研磨液僅為過氧化氫分子時，則化學反應最為劇烈，甚至可以看到氧氣的生成。無論使用何種研磨液，皆可以看到兩種磨耗機制，分別為銅對銅，以及銅對氧。當研磨液為雙氧水溶液時，研磨能力最強，其平均摩擦力也最大，同時顯示共價鍵的多寡會影響摩擦力的大小，以及明顯的stick -slip現象。此外，研磨壓力的改變對銅原子移除率的影響，遠大於改變磨耗速度。而就平均摩擦力而言，可以發現隨著研磨壓力的增加或是磨耗速度的提升，皆可以提升平均摩擦力。最後，當改變雙氧水的濃度時，可以發現過氧化氫濃度的提高，不但無法增加銅原子的移除率，反倒會有下降的趨勢，大約12%的濃度的磨耗效果為最好。

關鍵字: 分子動力學、化學機械研磨、摩擦力、化學反應、鍵結

The purpose of this study is to analyze the friction behavior and chemical properties
between the abrasive silicon dioxide particles and the copper metal conductor wire with different polishing slurries during copper chemical mechanical polishing (CMP) process at the microcosmic scale. Molecular dynamics simulations were
carried out using the program package LAMMPS with ReaxFF method. The
simulations of the nano-scale friction between the silicon dioxide abrasive and the
copper wire under different pressures and abrasion speeds with three different kinds of slurries were carried out, respectively. The results show that in the respect of
chemical reaction, the aqueous H2O2 solution produces the highest kinds of
compounds due to the continuous combination and separation between H2O2 and
water molecules. In the case with H2O2 molecules only, the reaction is the fiercest, and, moreover, capable of observing the generation of oxygens. Through the effects of mechanical sliding, Cu atoms can be removed in the form of clusters by fracturing of Cu-O bonds and Cu-Cu bonds with all three different slurries. With the aqueous H2O2 solution, the abrasion effect is the strongest, and the average friction force is the largest too. The continuous formation of the interface bonds strengthens the
interfacial friction force. Meanwhile, the phenomenon of stick-slip can be clearly observed. The effect of changing the pressure on the removal rate of copper atoms is more significant than changing the abrasion speed. It can be found that with the increase of pressure or the abrasion speed, the average friction force will be increased. Finally, the simulation results show that the effect of the concentration of
aqueous H2O2 on the removal rate of copper atoms is not monotonically dependent. The removal rate of copper atoms is the best at a concentration of about 12%.

Keywords : Molecular Dynamics, Chemical Mechanical Polishing, Nano Friction, Chemical reaction, Bond.

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