To provide a polishing composition for the CMP (chemomechanical polishing) processing for semiconductor devices each having a copper film and a tantalum compound, having such high selectivity as to be high in the polishing rate of the copper film but low in the polishing rate of the tantalum compound and affording the surface of the copper film with high smoothness.
The polishing composition is obtained by mixing ion-exchanged water filtered through a 0.5 μm cartridge filter with 10 pts.wt. of polymethyl methacrylate (PMMA) particles 30 nm in mean size as a polishing material, 2 pts.wt. of benzotriazole, 3 pts.wt. of hydrogen peroxide, 0.5 pt.wt. of citric acid, and 0.3 pt.wt. of a sorbitan lauric acid monoester ethylene oxide 20 mole adduct to effect a total weight of 100 pts.wt. followed by agitating the mixture with a high-speed homogenizer to effect homogeneous dispersion.
OGAWA TOSHIHIKO
KIMURA MICHIO
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