Korean Journal of Optics and Photonics (한국광학회지)

Optical Society of Korea (한국광학회)
권호 표지
DOI QR코드

DOI QR Code

Studies on Curved Diffractive Optical Elements in EUV

극자외선 영역에서 곡면 DOEs에 관한 연구

  • 최성을 (인천대학교 자연과학대Department of Physics, College of Natural Sciences, University of Incheon학 물리학과) ;
  • 이용우 (인천대학교 자연과학대학 물리학과) ;
  • 권명희 (인천대학교 자연과학대학 물리학과) ;
  • 김용후 (한국과학기술원)
  • Published : 2005.08.01
Download PDF
⟨ Previous Next ⟩

Abstract

Field performance of several different types of diffractive optical elements(DOEs) has been carried out. Using Zemax model, we have designed five different types of DOEs, such as transmissive flat-DOE, transmissive curved-DOE, reflective flat-DOE, reflective curved-DOE and parabolic mirror, We have applied two different wavelengths, i.e., 13 m(EUV) and 632.8 nm(visible) to above DOEs. Off_axis dominate aberrations and the diffraction limiting (Rayleigh limit) field angles have been investigated and compared at both wavelengths for each DOE. At diffraction limit, field angle of curved-DOEs was much greater than that of flat-DOEs for both transmission and reflective types. We also showed that dominated off_axis aberration of flat-DOEs was coma, but that of curved-DOEs was mixture of astigmatism and curvature of field. The measured field angle and expected OPD aberrations were well coincided with theoretical ones. Increasing the ratio of field angle with wavelength was more effective in curved-DOEs than flat-DOEs.

본 연구에서는 여러 형태의 회절광학요소의 field performance를 조사하였다. Zemax 프로그램을 이용하여 다섯 개의 회절광학요소, 즉 투과형 평면 DOE, 투과형 곡면 DOE, 반사형 포물면 DOE, 반사형 평면 DOE, 그리고 반사형 곡면 DOE를 설계하였다. 그리고 이들 회절광학요소에 극자외선 파장인 13 nm와 가시광선 파장인 632.8 nm를 적용시켰다. 이들 DOEs에 사입사 조명시의 회절 한계 하에서의 시야각의 크기 및 파장에 따른 특성, 그리고 주된 수차의 형태를 상호분석 비교하였다. 회절한계 하에서 투과 및 반사 형태 모두에서 곡면 DOEs의 시야각이 평면 DOEs의 시야각보다 훨씬 크다는 것을 알 수 있었다. 또한 사입사 경우에 평면 DOEs와 포물면경의 주된 수차는 코마이며, 곡면 DOEs의 주된 수차는 비점수차와 상면만곡의 혼합된 형태로 나타남을 알 수 있었다. 측정을 통하여 얻은 시야각의 크기와 수차의 종류가 이론적인 결과와 잘 일치함을 알 수 있었다. 또한 극자외선영역에서 평면형 DOEs에 비해 곡면형 DOEs의 field angle의 증가율이 가시광선에서보다 더 효과적임을 알 수 있었다.

Keywords

References

  1. H. P. Herzig and R. Dandliker, 'Holographic optical elements for use with semiconductor lasers,' in International Trends in Optics, J. W. Goodman, Ed., Academic Press, San Diego, 1991
  2. B. J. Chang, 'Dichromated gelatin holograms and their applications,' Opt. Eng., vol. 19, pp. 642-648, 1980
  3. D. H. Close, 'Holographic optical elements,' Opt. Eng., vol. 14, pp. 408-419, 1975
  4. F. Wyrowsky and O. Bryngdahl, 'Iterative Fourier Transform algorithm applied to computer holography,' J. Opt. Soc. Am., vol. A7, pp. 961-969, 1988
  5. J. L Homer and J. R. Leger, 'Pattern recognition with binary phase-only filters,' Appl. Opt., vol. 24, pp. 609-611, 1985 https://doi.org/10.1364/AO.24.000609
  6. G. E. Sommargren and L. G. Seppala, 'Condenser Optics, Partial coherence and imaging for soft X-ray projection lithography,' Appl. Opt., vol. 32, no. 34, pp. 6938-6944, 1993 https://doi.org/10.1364/AO.32.006938
  7. S.J. Walker and J. Jahns, 'Optical clock distribution using integrated free-space optics,' Opt. Commun., vol. 90, pp. 359-371, 1992 https://doi.org/10.1016/0030-4018(92)90290-8
  8. Andrew M. Hawryluk and Natale M. Ceglio, 'Wavelength considerations in soft X-ray projection lithography,' Appl. Opt., vol. 32, no. 34, pp. 7062-7067, 1993 https://doi.org/10.1364/AO.32.007062
  9. L. A. Hackel and R. J. Beach, 'Laser driver for soft X-ray lithography,' Appl. Opt., vol. 32, pp. 6914-6919, 1993 https://doi.org/10.1364/AO.32.006914
  10. R. L. Kauffman, D. W. Phillion, and R. Spitzer, 'X-ray production at 13 nm from laser-produced plasmas for projection X-ray lithography applications,' Appl. Opt., vol. 32, pp. 6897-6900, 1993 https://doi.org/10.1364/AO.32.006897
  11. M. Young, 'Zone plates and their aberrations,' J. Opt. Soc. Am., vol. 62, no. 8, pp. 972-976, 1972 https://doi.org/10.1364/JOSA.62.000972
  12. A. M. Hawryluk and L. G. Seppala, 'Soft X-ray projection lithography using an X-ray reduction camera,' J. Vac. Sci. Tech., vol. B6, pp. 2162-2166, 1988
  13. H. Kinoshita, K. Kurihara, Y. Ishii, and Y. Torri, 'Soft X-ray reduction lithography using multi-layer mirrors,' J. Vac. Sci. Tech., vol. B7, pp. 1648-1651, 1989
  14. O. R. Wood II, W. T. Silfvast, and T. E. Jewell, 'Shortwavelength annular-field optical system for imaging tenthmicron features,' J. Vac. Sci. Tech., vol. B7, pp. 1613-1615, 1989
  15. D. M. Tennant, L. A. Fetter, L. R. Harriott, A. A. Mac Dowell, P. P. Mulgrew, J. Z. Pastalan, W. K. Waskiewicz, K. L. Windt, and O. R. Wood II, 'Mask technologies for soft X-ray micro lithography at 13 rm,' Appl. Opt., vol. 32, no. 34, pp. 7007-7011, 1993 https://doi.org/10.1364/AO.32.007007
  16. Cheng Wang and David L. Shealy, 'Differential equation design finite-conjugate reflective systems,' Appl. Opt., vol. 32, pp. 1179, 1993 https://doi.org/10.1364/AO.32.001179
  17. Tanys E. Jewell, J. Michael Rodgers and Kevin K. Thompson, 'Reflective systems design study for soft X-ray projection lithography,' J. Vac. Sci. Technol., vol. B8, no. 6, pp. 1519-1523, 1990
  18. Young Min Cho and Sang Soo Lee, 'Holosymmetric 4 mirror optical system(mag.=+ I) for soft X-ray projection lithography,' J. National Academy of Science, Korea, vol. 33, pp. 1, 1994
  19. Dong Hee Lee, Hong Jin Kong and Sang Soo Lee, 'Five mirror system derived from the numerical solutions of all zero 3rd-order aberrations and zero 5th-order spherical aberration for deep-ultraviolet optical lithography,' Kogaku J. Optical Society of Japan, vol. 23, pp. 198-206, 1994
  20. T. D. Milster, R. M. Trusty, M. S. Wang, F. F. Froehlich, and J. K. Erwin, 'Micro-optic lens for data storage,' in Optical Data Storage, James J. Burke, Thomas A. Shull, Nobutake Imamura, Eds., Proc. SPIE, vol. 1499, pp. 286-292, 1991
  21. R. M. Trusty, 'Micro-Fresnel Lens on a Spherical Shell Substrate,' Thesis, 1990
  22. Edita Tejnil, K. A . Goldberg, S. Lee, H. Medecki, P. J. Batson, P. E. Denham, A. A. MacDowell, J. Bokor, and D. Attwood, 'At-wavelength interferometry for extreme ultraviolet lithography,' J. Vac. Sci. Technol., vol. B15, no. 6, pp. 2455-2461, 1997