Study on Oxidant in Chemical Mechanical Polishing of Copper

In this paper, the polishing experiment of copper was carried out. According to the experimental data, when FeCl3 was selected as oxidant, the material removal rate increases gradually with the increase of oxidant concentration. When other conditions remain unchanged, the material removal rate with larger abrasives was higher than that of smaller abrasives, and the material removal rate of pressure 3 psi was higher than that of pressure 2 psi, and the surface roughness became smaller and smaller. When the abrasive size was 1 µm, oxidant concentration was 5 g/L and the pressure was 3 psi, the material removal rate reaches 206.9 nm/min and the surface roughness reached 8 nm. When the type of oxidant was chosen as the variable, the material removal rate of the mixture of FeCl3 and H2O2 was the highest, the maximum removal rate was 105.45 nm/min when the abrasive size was 1 µm and polishing speed was 80 r/min. The surface roughness was the smallest when FeCl3 was used as oxidant and Ra reaches the smallest 5 nm under the conditions of the abrasive size was 1 µm and polishing speed 80 r/min. The results can be used as a reference for further research the ingredients of polishing slurry in the chemical mechanical polishing of copper.