Effect of Pressure and Initial Polymer Resist Thickness on Low Temperature Nanoimprint Lithography

저온 나노임프린트 공정에서 압력과 폴리머 레지스트 초기 두께의 영향

  • 김남웅 (서울대학교 기계항공공학부 대학원) ;
  • 김국원 (순천향대학교 기계공학과) ;
  • 신효철 (서울대학교 기계항공공학부)
  • Published : 2009.02.15

Abstract

A major disadvantage of thermal nanoimprint lithography(NIL) is the thermal cycle, that is, heating over glass transition temperature and then cooling below it, which requires a significant amount of processing time and limits the throughput. One of the methods to overcome this disadvantage is to make the processing temperature lower Accordingly, it is necessary to determine the effects on the processing parameters for thermal NIL at reduced temperatures and to optimize the parameters. This starts with a clear understanding of polymer material behavior during the NIL process. In this work, the squeezing and filling of thin polymer films into nanocavities during the low temperature thermal NIL have been investigated based upon a two-dimensional viscoelastic finite element analysis in order to understand how the process conditions affect a pattern quality; Pressure and initial polymer resist thickness dependency of cavity filling behaviors has been investigated.

Keywords

References

  1. Chou, S., and Krauss, P., 1997, "Imprint Lithography with Sub-10nm Feature Size and High Throughput," Microelectron. Eng., Vol. 35, pp. 237-240. https://doi.org/10.1016/S0167-9317(96)00097-4
  2. Guo, L. J., 2004, "Recent Progress in Nanoimprint Technology and Its Applications," J. Phys. D: Appl. Phys., Vol. 37, pp. R123-R141. https://doi.org/10.1088/0022-3727/37/11/R01
  3. Hirai, Y., Fujiwara, M., Okuno, T., Tanaka, Y., Endo, M., Irie, S., Nakagawa, K., and Sasago, M., 2001, "Study of the Resist Deformation in Nanoimprint Lithography," J. Vac. Sci. Technol. B, Vol. 19, pp. 2811-2815. https://doi.org/10.1116/1.1415510
  4. Hirai, Y., Konish, T., Yoshikawa, T., and Yoshida, S., 2004, "Simulation and Experimental Study of Polymer Deformation in Nanoimprint Lithography," J. Vac. Sci. Technol. B, Vol. 22, pp. 3288-3293. https://doi.org/10.1116/1.1826058
  5. Kim, N. W., Kim, K. W., and Sin, H.-C., 2007, "A Viscoelasitc Finite Element Analysis of Thermal Nanoimprint Lithography Process," Journal of the Microelectronics & Packaging Society, Vol. 14, No. 4, pp. 1-7.
  6. Young, W. B., 2005, "Analysis of the Nanoimprint Lithography with a Viscous Model," Microelectron. Eng., Vol. 77, pp. 405-411. https://doi.org/10.1016/j.mee.2005.01.024
  7. Rowland, H. D., and King, W. P., 2004, "Polymer Deformation and Filling Modes During Microembossing," J. Micromech. Microeng., Vol. 14, pp. 1625-1632. https://doi.org/10.1088/0960-1317/14/12/005
  8. Son, J. W,. Song, N. H., Rhim, S. H., and Oh, S. I., 2007, "Prediction of Defects in Nano-imprint Lithography Using FEM Simulation," Key Eng. Mater., Vols. 345-346, pp. 665-668. https://doi.org/10.4028/www.scientific.net/KEM.345-346.665
  9. Khang, D. Y., and Lee, H. H., 2000, "Room temperature Imprint Lithography by Solvent Vapor Treatment," Appl. Phys. Lett., Vol. 76, No. 7, pp. 870-872. https://doi.org/10.1063/1.125613
  10. Alkaisi, M. M., Blaikie, R. J., and McNab, S. J., 2001, "Low Temperature Nanoimprint Lithography Using Silicon Nitride Molds," Microelectron. Eng., Vols. 57-58, pp. 367-373. https://doi.org/10.1016/S0167-9317(01)00435-X
  11. McLoughlin, J. R., and Tobolsky, A.V., 1952, "The Viscoelastic Behavior of Polymethyl Mechacrylate," Journal of Colloid Science, Vol. 7, pp. 555-568. https://doi.org/10.1016/0095-8522(52)90039-1
  12. Takahashi, M., Shen, M. C., Shen, Taylor, R. B., and Tobolsky, A.V., 1964, "Master Curves for Some Amorphous Polymers," J. Appl. Polym. Sci., Vol. 8, pp. 1549-1561. https://doi.org/10.1002/app.1964.070080405
  13. Cost, T. L. and Becker, E. B., 1970, "A Multidata Method of Approximate Laplace Transform Inversion," Int. J. Numer. Methods Eng., Vol. 2, pp. 207-219. https://doi.org/10.1002/nme.1620020206
  14. Juang, Y. J., Lee, L. J., and Koelling, K. W., 2002, "Hot Embossing in Microfabrication. Part I: Experimental," Polym. Eng. Sci., Vol. 42, pp. 539-550. https://doi.org/10.1002/pen.10970
  15. Kim, K. W., and Kim, N. W., 2008, "Analytical Approach of Polymer Flow in Thermal Nanoimprint Lithography," Trans. of the KSMTE, Vol. 17, No. 3, pp. 20-26.
  16. Schift, H., and Heyderman, L. J. in: Sotomayor Torres C. M. (Ed.), 2003, Alternative Lithography, Kluwer Academic Plenum, New York.