Effect of Pad Thickness on Removal Rate and Within Wafer Non-Uniformity in Oxide CMP

산화막 CMP에서 패드 두께가 연마율과 연마 불균일도에 미치는 영향

  • Published : 2010.05.01


The polishing pad is important element for polishing characteristic such as material removal rate(MRR) and within wafer non-uniformity(WIWNU) in the chemical mechanical planarization(CMP). The result of the viscoelasticity measurement shows that 1st elastic modulus is increased and 2nd elastic modulus is decreased when the top pad is thickened. The finite element analysis(FEA) was conducted to predict characteristic of polishing behavior according to the pad thickness. The result of polishing experiment was similar with the FEA, and it shows that the 1st elastic modulus affects instantaneous deformation of pad related to MRR. And the 2nd elastic modulus has an effect on WIWNU due to the viscoelasticity deformation of pad.


Chemical mechanical planarization (CMP);Pad thickness;Viscoelasticity;Material removal rate (MRR);Within wafer non-uniformiy (WIWNU)


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