Effect of Flow Rate of Slurry in Micro-Channels on the Consistency of Polishing Rate

Abstract:

According to the Bernoulli equation and Darcy formula, the flow model of slurry in micro-channels was established, it indicated that slurry viscosity is the main factor affecting the slurry mean velocity. According to the characteristics that liquid viscosity is mainly determined by the liquid temperature and the property that mechanical friction can improve the liquid temperature, the effects of slurry temperature, working pressure and polishing speed on the heterogeneity of polishing rate were investigated. The results showed that the effect of removal rate of each parameter on the central part of the copper film can be described as: slurry temperature > working pressure > polishing speed. In order to obtain the best planarization process, through the central composite experimental method, the technological parameters were optimized regarding the heterogeneity of polishing rate as response value. It was finally concluded that: when the slurry temperature was 21.60°C, the working pressure was 8.83kpa, the system speed was 43.92rpm, the predicted minimum value of the heterogeneity of polishing rate (HOPR) was 0.0574.

• Periodical: Key Engineering Materials (Volumes 645-646)
• Pages: 462-468
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.645-646.462
• Online since: May 2015
• Authors: Yan Li, Ming Sun, Yu Ling Liu*, Ao Chen Wang, Ji Ying Tang, Shi Yan Fan
• Keywords: Bernoulli Equation, Central Composite Experimental Method, Chemical Mechanical Planarization, Heterogeneity of Polishing Rate, Heterogeneity of Step Height Difference

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