Effect of Viscosity on Ceria Abrasive Removal in the Buffing CMP Process

Abstract:

In chemical mechanical planarization (CMP) processes, ceria is generally used as the abrasive . After the CMP process, many ceria particles adhere to the wafer surface and must be removed prior to subsequent processing. In this study, the effect of varied viscosity was investigated during the buffing CMP process for ceria particle removal. After contaminating the wafer surface with ceria slurry, the ceria particles were removed through the buffing CMP process. The wafer surface was analyzed through inductively coupled plasma mass spectrometry (ICP-MS) to confirm cleaning efficiency. The ICP-MS data showed that, as buffing CMP solution viscosity increased, cleaning efficiency improved. These results suggest that increasing the viscosity of the buffing CMP solution improves its effectiveness in removing ceria particles.

• Periodical: Solid State Phenomena (Volume 314)
• Pages: 247-252
• DOI: https://doi.org/10.4028/www.scientific.net/SSP.314.247
• Online since: February 2021
• Authors: Juhwan Kim, Seokjun Hong, Chulwoo Bae, Yutaka Wada, Hirokuni Hiyama, Satomi Hamada, Taesung Kim*
• Keywords: Buffing, CMP, Post CMP Cleaning, Viscosity

References

[1] P.B. Zantye, A. Kumar, A. Sikder, Chemical mechanical planarization for microelectronics applications, Materials Science and Engineering: R: Reports 45(3-6) (2004) 89-220.

DOI: 10.1016/j.mser.2004.06.002

[2] J. Cheng, T. Wang, Y. He, X. Lu, Material removal mechanism of copper chemical mechanical polishing in a periodate-based slurry, Applied Surface Science 337 (2015) 130-137.

DOI: 10.1016/j.apsusc.2015.02.076

[3] M.R. Oliver, Chemical-mechanical planarization of semiconductor materials, Springer Science & Business Media2013.

[4] A.A. Busnaina, H. Lin, N. Moumen, J.-w. Feng, J. Taylor, Particle adhesion and removal mechanisms in post-CMP cleaning processes, IEEE transactions on semiconductor manufacturing 15(4) (2002) 374-382.

DOI: 10.1109/tsm.2002.804872

[5] J. Seo, A. Gowda, S. Babu, Almost Complete Removal of Ceria Particles Down to 10 nm Size from Silicon Dioxide Surfaces, ECS Journal of Solid State Science and Technology 7(5) (2018) P243-P252.

DOI: 10.1149/2.0131805jss

[6] S. Hong, J. Kim, J. Won, N. Qureshi, S. Chae, Y. Wada, H. Hiyama, S. Hamada, T. Kim, A Water Polishing Process to Improve Ceria Abrasive Removal, ECS Journal of Solid State Science and Technology 8(8) (2019) P430.

DOI: 10.1149/2.0171908jss

[7] J.B. Segur, H.E. Oberstar, Viscosity of glycerol and its aqueous solutions, Industrial & Engineering Chemistry 43(9) (1951) 2117-2120.

DOI: 10.1021/ie50501a040