A Study on the Formation of Air Bubble by the Droplet Volume and Dispensing Method in UV NIL

UV NIL공정에서 액적의 양과 도포방법에 따른 기포형성 연구

  • Lee, Ki Yeon (Department of Mechanical Engineering, SoonChunHyang University) ;
  • Kim, Kug Weon (Department of Mechanical Engineering, SoonChunHyang University)
  • 이기연 (순천향대학교 기계공학과) ;
  • 김국원 (순천향대학교 기계공학과)
  • Received : 2013.07.01
  • Accepted : 2013.09.06
  • Published : 2013.09.30


Nanoimprint lithography (NIL) is an emerging technology enabling cost-effective and high-throughput nanofabrication. Recently, the major trends of NIL are high throughput and large area patterning. UV curable type NIL (UV NIL) can be performed at room temperature and low pressure. And one advantage of UV NIL is that it does not need vacuum, which greatly simplifies tool construction, so that vacuum oprated high-precision stages and a large vacuum chamber are no longer needed. However, one key issue in non-vacuum environment is air bubble formation problem. Namely, can the air bubbles be completely removed from the resist. In this paper, the air bubbles formation by the method of droplet application in UV NIL with non-vacuum environment are experimentally studied. The effects of the volume of droplet and the number of dispensing points on air bubble formation are investigated.


Air bubble formation;Dispensing method;Droplet volume;Non-vacuum environment;UV NIL


  1. Chou, S. and Krauss, P., "Imprint lithography with sub-10nm feature size and high throughput," Microelectronic Engineering, Vol. 35, pp. 237-240, 1997. DOI:
  2. Guo, L. J., "Recent progress in nanoimprint technology and its applications," J. Phys. D: Appl. Phys., Vol. 37, pp. R123-R141, 2004. DOI:
  3. Kim, N. W., Kim, K. W., and Sin, H.-C., "Finite element analysis of low temperature thermal nanoimprint lithography using a viscoelastic model," Microelectronic Engineering, Vol. 85, pp. 1858-1865, 2008. DOI:
  4. Lee, K. Y., and, Kim, K. W., "A study on the filling process and residual layer formation in nanoimprint lithography process," Journal of the Korea Academia-Industrial coorperation Society, Vol. 13, No. 9, pp. 3835-3840, 2012.
  5. Kim, N. W., Kim, K. W., and Sin, H.-C., "A mathematical model for slip phenomenon in a cavity-filling process of nanoimprint lithography," Microelectronic Engineering, Vol. 86, pp. 2324-2329, 2009. DOI:
  6. Morihara, D., Hiroshima, H., and Hirai, Y., "Numerical study on bubble trapping in UV-nanoimprint lithography," Microelectronic Engineering, Vol. 86, No. 4-6, pp. 684-687, 2009. DOI:
  7. Nagaoka, Y., Morihara, D., Hiroshima, H., and Hirai, Y., "Simulation study on bubble trapping in UV nanoimprint lithography," Journal of Photopolymer Science and Technology, Vol. 22, No. 2, pp. 171-174, 2009. DOI:
  8. Hiroshima, H., Komuro, M., Kasahara, N., Kurashima, Y., and Taniguchi, J., "Elimination of pattern defects of nanoimprint under atmospheric condition," Japanese Journal of Applied Physics, Vol. 42, pp. 3849-3853, 2003. DOI:
  9. Hiroshima, H., and Komuro, M., 2007, "Control of bubble defects in UV nanoimprint," Japanese Journal of Applied Physics, Vol. 46, No. 9B, pp. 6391-6394. DOI:
  10. Liang, X., Tan, H., Fu, Z., and Chou, S. Y., "Air bubble formation and dissolution in dispensing nanoimprint lithography," Nanotechnology, Vol. 18, No. 2, pp. 1-7, 2007. DOI:
  11. Reddy, S., Schunk, P. R., and Bonnecaze, R. T., "Dynamics of low capillary number interfaces moving through sharp features," Physics of Fluids, Vol. 17, No. 12, pp. 122104-1-6, 2005. DOI:
  12. Reddy, S., and Bonnecaze, R. T., "Simulation of fluid flow in the step and flash imprint lithography process," Microelectronic Engineering, Vol. 82, No. 1, pp. 60-70, 2005. DOI:
  13. Seok, J.M. and Kim, N.W., "Analytic and numerical study for air bubble defect of UV-NIL process", Journal of the Korean Society of Manufacturing Technology Engineers, Vol. 21, No. 3, pp. 473-478, 2012. DOI:
  14. Yoo, S.H., "The 3D investigation of bubble defect during the fabrication of anti-reflective pattern through UV-NIL", M.D. Thesis, Seoul National University, 2012.