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http://dx.doi.org/10.7317/pk.2014.38.5.640

Analysis of Coating Uniformity through Unsteady and Steady State Computer Simulation in Slot Coating  

Woo, Jeong-Woo (Department of Product Design Manufacturing Engineering, Graduate School of Seoul National University of Science and Technology)
Sung, Dal-Je (Narae Nanotech)
Lyu, Min-Young (Department of Mechanical System Design Engineering, Seoul National University of Science and Technology)
Publication Information
Polymer(Korea) / v.38, no.5, 2014 , pp. 640-644 More about this Journal
Abstract
As a process of plat panel display production, slot coating is widely used for the coating of photoresist on a wide glass substrate. A uniform coating thickness is important, and the coating uniformity is divided into nozzle and machine directions. The machine and nozzle directions coating uniformities are influenced by the operation condition of coater and flow uniformity inside the die, respectively. Non-uniform coating during steady coating process occurs according to those factors, however, non-uniform coating along the machine and nozzle directions has been observed at the beginning of coating by unsteady flow. In this study, steady and unsteady state flow simulations have been performed and compared with experiment to examine the causes of non-uniform coating. Computational results exhibited that it took a time to get a uniform pressure distribution at whole inside the die, and during this period of time edge regions showed lower exit velocity compared with center region. Subsequently edge regions had thinner coated layers than center region. However edge regions showed higher exit velocity than center region after steady state, and this made edge regions had thicker coated layer than center region.
Keywords
slot coating; photo resist; wide glass substrate; coating quality; unsteady state simulation;
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1 Y. R. Chang, C. F. Lin, and T. J. Liu, Polym. Eng. Sci., 49, 1158 (2009).   DOI   ScienceOn
2 S. J. Weinstein and K. J. Ruschak, Annu. Rev. Fluid Mech., 36, 29 (2004).   DOI   ScienceOn
3 Y. Sun and M. Gupta, Int. Polym. Proc., 20, 380 (2005).   DOI
4 O. J. Romero, L. E. Scriven, and M. D. S. Carvalho, Am. Inst. Chem. Eng., 52, 447 (2006).   DOI   ScienceOn
5 T. Wu, B. Jiang, S. Xu, and C. Bi, Polym. Eng. Sci., 46, 406 (2006).   DOI
6 K. Meng, X. Wang, and X. Huang, Polym. Eng. Sci., 49, 354 (2009).   DOI   ScienceOn
7 O. J. Romero, L. E. Scriven, and M. S. Carvalho, J. Non-Newton. Fluid, 138, 63 (2006).   DOI   ScienceOn
8 K. H. Chung, M. P. Kim, and C. W. Kang, Electron Devices Meeting, IEDM'02, 1, 385 (2002).
9 S. I. Youn, S. Y. Kim, D. M. Shin, J. S. Lee, H. W. Jung, and J. C. Hyun, Korea-Aust. Rheol. J., 18, 209 (2006).
10 J. W. Kim, J. D. Chung, and S. G. Kim, Journal of the Semiconductor & Display Equipment Technology, 3, 41 (2004).
11 O. J. Romeo, W. J. Suszynski, L. E. Scriven, and M. S. Carvalho, J. Non-Newton. Fluid, 118, 137 (2004).   DOI