Journal of the Korean Society for Precision Engineering (한국정밀공학회지)

Korean Society for Precision Engineering (한국정밀공학회)
권호 표지

Study on Process Parameters of a SU-8 Resin in Two-photon Streolithography for the Fabrication of Robust Three-dimensional Microstructures

SU-8 레진을 이용한 이광자 흡수 광조형 공정에서 고강성 3 차원 마이크로 형상 제작을 위한 공정 변수 분석

  • 손용 (한국과학기술원 기계공학과) ;
  • 임태우 (한국과학기술원 기계공학과) ;
  • 이신욱 (한국과학기술원 물리학과) ;
  • 공홍진 (한국과학기술원 물리학과) ;
  • 박상후 (부산대학교 기계공학과) ;
  • 양동열 (한국과학기술원 기계공학과)
  • Published : 2008.01.01
Download PDF
⟨ Previous Next ⟩

Abstract

Two-photon stereolithography (TPS) is recognized as a useful process for the fabrication of three-dimensional microstructures. Recently, the need for a two-photon curable resin with high strength increases as 3-D moicrostructures of high aspect ratio or large scale of several hundreds micrometers are required for applications of nano/micro devices in IT/BT. In this work, process parameters of TPS employing the SU-8 which is a representative two-photon curable resin with high strength have been studied for the precise fabrication of 3-D microstructures with high strength. The pre-baking and post-baking processes are studied and the parameter study of the SU-8 in TPS is conducted. Through this work, very small roughness of 12 nm and the minimum aspect ratio of ${\sim}1$ which provides a precise accumulation of layers could be obtained. Using the conditions studied in this work, some 3-D examples are fabricated.

Keywords

References

  1. Kawata, S., Sun, H. B., Tanaka, T. and Takada, K., 'Finer features for functional microdevices,' Nature, Vol. 412, No. 16, pp. 697-698, 2001 https://doi.org/10.1038/35089130
  2. Serbin, J., Egbert, A., Ostendorf, A. and Chichkov, B. N., 'Femtosecond laser-induced two-photon polymer -ization of inorganic-organic hybrid materials for applications in photonics,' Optics Letters, Vol. 28, No. 5, pp. 301-303, 2003 https://doi.org/10.1364/OL.28.000301
  3. Yang, D. Y., Park, S. H., Lim, T. W., Kong, H. J., Yi, S. W., Yang, H. K. and Lee, K. S., 'Ultraprecise Micro-reproduction of a Three-dimensional Artistic Sculpture by Multipath Scanning Method in Two-photon Photopolymerization,' Appl. Phys. Lett., Vol. 90, Issue 1, pp. 013113-1 - 013113-3, 2007 https://doi.org/10.1063/1.2425022
  4. Lim, T. W., Park, S. H., Yang, D. Y., Yi, S. W. and Kong, H. J., 'Development of contour offset algorithm (COA) in nRP process for fabricating nano-precision features,' J. KSPE, Vol. 21, No. 6, pp. 160-166, 2004
  5. Park, S. H., Lee, S. H., Yang, D. Y., Kong, H. J. and Lee, K. S., 'Subregional slicing method to increase 3D nanofabrication efficiency in two-photon polymerization,' Appl. Phys. Lett., Vol. 87, Issue 15, pp. 154108-1 - 154108-3, 2005 https://doi.org/10.1063/1.2103393
  6. Park, S. H., Lim, T. W., Yang, D. Y., Kim, R. H. and Lee, K. S., 'Improvement of Spatial Resolution in Nano-Stereolithography Using Radical Quencher,' Macromolecular Research, Vol. 14, No. 5, pp. 559-564, 2006 https://doi.org/10.1007/BF03218724
  7. Deubel, M., Freymann, G. V., Wegener, M., Pereira, S., Busch, K. and Soukoulis, C. M., 'Direct laser writing of three-dimensional photonic-crystal templates for telecommunications,' Nature Materials, Vol. 3, Issue 7, pp. 444-447, 2004 https://doi.org/10.1038/nmat1155
  8. Seet, K. K., Mizeikis, V., Matsuo, S., Juodkazis, S. and Misawa, H., 'Three-dimensional spiral-architecture photonic crystals obtained by direct laser writing,' adv. Mater., Vol. 17, No. 5, pp. 541-545, 2005 https://doi.org/10.1002/adma.200401527
  9. Teh, W. H., Dürig, U., Salis, G., Harbers, R., Drechsler, U., Mahrt, R. F., Smith, C. G. and Güntherodt, H. J., 'SU-8 for real three-dimensional subdiffraction-limit two-photon microfabrication,' Appl. Phys. Lett., Vol. 84, No. 20, pp. 4095-4097, 2004 https://doi.org/10.1063/1.1753059
  10. Juodkazis, S., Mizeikis, V., Seet, K. K., Miwa, M. and Misawa, H., 'Two-photon lithography of nanorods in SU-8 photoresist,' Nanotechnology, Vol. 16, No. 6, pp. 846-849, 2005 https://doi.org/10.1088/0957-4484/16/6/039
  11. Park, S. H., Lim, T. W., Jeong, C. G., Yang, D. Y., Yi, S. W., Lee, S. K. and Kong, H. J., 'Fundamental process development of a ultramicro-stereolitho-graphy using a femto-second laser for manufacturing nano-scaled features,' J. KSPE, Vol. 21, No. 3, pp. 180-187, 2004
  12. Zhang, J., Tan, K. L., Hong, G. D., Yang, L. J. and Gong, H. Q., 'Polymerization optimization of SU-8 photoresist and its applications in microfluidic systems and MEMS,' J. Micromech. Microeng. Vol. 11, No. 1, pp. 20-26, 2001 https://doi.org/10.1088/0960-1317/11/1/304
  13. Feng, R. and Farris, R. J., 'Influence of processing conditions on the thermal and mechanical properties of SU8 negative photoresist coatings,' J. Micromech. Microeng. Vol. 13, No. 1, pp. 80-88, 2003 https://doi.org/10.1088/0960-1317/13/1/312
  14. Liu, G., Tian, Y. and Kan, Y., 'Fabrication of high-aspect-ratio microstructures using SU8 photoresist,' Microsystem Technologies, Vol. 11, No. 4, pp. 343-346, 2005 https://doi.org/10.1007/s00542-004-0452-x
  15. Sun, H. B., Takada, K., Kim, M. S., Lee, K. S. and Kawata, S., 'Scaling laws of voxels in two-photon photopolymerization nanofabrication,' Appl. Phys. Lett., Vol. 83, No. 6, pp. 1104-1106, 2003 https://doi.org/10.1063/1.1599968