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.
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Xinchun LU. He received the BS and MS degrees in material science and engineering from Jilin University of Technology, Changchun, China, in 1988 and 1991, respectively, and the PhD degree in the same field from the Institute of Metal Research, Chinese Academy of Sciences, in 1994.
He is a chair professor of Changjiang Scholars in the Department of Precision Instruments and Mechanology of Tsinghua University, China, and is a member of the international executive committee of ICPT. His current areas of research include micro-nano fabrication technology, the theory and applications of the micro-nano tribology of the surface and interface, and equipment and processes of chemical mechanical polishing. He is the author or coauthor of over 100 journal publications and conference proceedings papers. He holds over 16 patents in the area of CMP equipment.
Prof. Lu was the recipient of the Trans-Century Training Program of the National Ministry of Education, and the National Science Found for Distinguished Young Scholars of China. He has received numerous national awards, including the Award for National Science Development (grade two), and the Science & Technology Advancement Award (grade one), from the National Ministry of Education.
Dewen ZHAO. He received the BS degree in mechanical engineering from Huazhong University of Science and Technology, Wuhan, China, in 2007, and the PhD degree in mechanical engineering from Tsinghua University, Beijing, China in 2012. He received the Bronze Medal of HIWIN Doctoral Dissertation Award in 2013. Dr. Zhao is currently a postdoctoral research fellow at Tsinghua University, Beijing, China. He has more than 10 papers indexed by SCI, and 9 authorized national invention patents. His major research areas include chemical mechanical polishing equipment and principles, tribology, and process monitoring.
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Zhao, D., Lu, X. Chemical mechanical polishing: Theory and experiment. Friction 1, 306–326 (2013). https://doi.org/10.1007/s40544-013-0035-x
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DOI: https://doi.org/10.1007/s40544-013-0035-x