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For several decades, chemical mechanical polishing (CMP) has been the most widely used planarization method in integrated circuits manufacturing. The final polishing results are affected by many factors related to the carrier structure, the polishing pad, the slurry, and the process parameters. As both chemical and mechanical actions affect the effectiveness of CMP, and these actions are themselves affected by many factors, the CMP mechanism is complex and has been a hot research area for many years. This review provides a basic description of the development, challenges, and key technologies associated with CMP. We summarize theoretical CMP models from the perspectives of kinematics, empirical, its mechanism (from the viewpoint of the atomic scale, particle scale, and wafer scale), and its chemical–mechanical synergy. Experimental approaches to the CMP mechanism of material removal and planarization are further discussed from the viewpoint of the particle wear effect, chemical–mechanical synergy, and wafer–pad interfacial interaction.


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Chemical mechanical polishing: Theory and experiment

Show Author's information Dewen ZHAOXinchun LU( )
State Key Laboratory of Tribology, Tsinghua University, Beijing, 100084, China

Abstract

For several decades, chemical mechanical polishing (CMP) has been the most widely used planarization method in integrated circuits manufacturing. The final polishing results are affected by many factors related to the carrier structure, the polishing pad, the slurry, and the process parameters. As both chemical and mechanical actions affect the effectiveness of CMP, and these actions are themselves affected by many factors, the CMP mechanism is complex and has been a hot research area for many years. This review provides a basic description of the development, challenges, and key technologies associated with CMP. We summarize theoretical CMP models from the perspectives of kinematics, empirical, its mechanism (from the viewpoint of the atomic scale, particle scale, and wafer scale), and its chemical–mechanical synergy. Experimental approaches to the CMP mechanism of material removal and planarization are further discussed from the viewpoint of the particle wear effect, chemical–mechanical synergy, and wafer–pad interfacial interaction.

Keywords:

chemical mechanical polishing (CMP), CMP model, planarization mechanism, wafer–pad interaction, uniformity
Received: 25 October 2013 Accepted: 24 November 2013 Published: 12 December 2013 Issue date: December 2013
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Publication history

Received: 25 October 2013
Accepted: 24 November 2013
Published: 12 December 2013
Issue date: December 2013

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© The author(s) 2013

Acknowledgements

The authors appreciate the financial support provided by the Science Fund for Creative Research Groups (Grant No. 51021064), and the National Natural Science Foundation of China (Grant No. 51305227). The authors would like to thank Enago (www.enago.cn) for the English language review.

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