Article in Russian
For citation: Zoric N.D., Livshits I.L., Okishev S.G., Somova E.A., Anitropov R.V., Letunovskaya M.V. Design method for complex lenses by dividing them into parts.
Scientific and Technical Journal of Information Technologies, Mechanics and Optics, 2017, vol. 17, no. 2, pp. 234–241 (in Russian). doi: 10.17586/2226-1494-2017-17-2-234-241
Abstract
The paper deals with a method of ultraviolet objective design for optical lithography. The approach to such complex lens design is to split the complex objective into the two simpler ones. The front objective has the object at the finite distance and the image placed at the infinity. The second (receiver) part of lithographic lens acts as an ordinary photographic objective. The separate parts of complex objective have been calculated independently and combined into a single complex lens with the subsequent cross-cutting optimization of parameters. The two independent parts of lithographic lens are combined in an aperture stop plane. The both lenses are designed according to the scheme with an external entrance pupil. In order to generate starting points of optical systems, we have used the elements of artificial intelligence in lens design software, SYNOPSYS, OSD. The proposed method describes the steps of obtaining feasible starting points and solves the typical optimization challenges within the systems with high aperture. The calculations of characteristics are explained on an example of bi-telecentric lithographic objective. The objective is optimized as a diffraction-limited system for the spectral range from 362 to 368 mm where the principal color is 365 nm. The Strehl ratio at the principal color of 365 nm at the edge of the field is equal to 0.989. The objective has a total track of 630 mm, consists of the 18 lenses with 4 aspherical surfaces. The total magnification is 0.2, with the distortion less than 1 %. The image size is 22×22 mm2. We have used S-FPL53, S-FPL51Y, BAL15Y glass material for the positive lenses and PBM2Y, PBL25Y for the negative lenses. The simulated internal transmission after the adding of antireflection coating is equal to 43 %.
Keywords: lithography, optical design, composite lens, UV, artificial intelligence, starting point
Acknowledgements. References
1. Zoric N., Livshits I., Dilworth D., Okishev S. Design of an ultraviolet projection lens by using a global search algorithm and computer optimization.
Advanced Optical Technologies, 2016, vol. 6, no. 1, pp. 31–38. doi:
10.1515/aot-2016-0058
2. Livshits I. L., Sal'nikov A.V., Cho U. Choosing the starting system for designing objectives. Journal of Optical Technology, 2007, vol. 74, no. 11, pp. 783–786.
3. Harriott L.R. Limits of lithography.
Proceedings of the IEEE, 2001, vol. 89, no. 3, pp. 366–374. doi:
10.1109/5.915379
4. Shafer D.R. Doing more with less. Proceedings of SPIE, 1995, vol. 2537, pp. 2–12.
5. Rusinov M.M. Kompozitsiya Opticheskikh Sistem [Composition of Optical Systems]. Leningrad, Mashinostroenie Publ., 1989, 383 p.
7. Levinson H.J. Principles of Lithography. 2nd ed. Bellingham, SPIE Press, 2005, 438 p.
8. Livshits I.L., Zoric N. A concept of ultraviolet lithography system and design of its rear part using artificial intelligence for starting design. Proc. 4th Int. Conf. on Photonics, Optics and Laser Technology. Rome, Italy, 2016, pp. 82–86.
9. SYNOPSYS™ Optical Systems Design, Inc.
10. Zemax OpticStudio_14.1 SP1. Radiant Zemax LLC, 2015.
11. Dilworth D.C., Shafer D. Man versus machine: a lens design challenge.
Proceedings of SPIE, 2013, vol. 8841, art. 88410G. doi:
10.1117/12.2022871
12. Bociort F., van Turnhout M. Saddle points reveal essential properties of the merit-function landscape.
SPIE Newsroom, 2008. doi:
10.1117/2.1200811.1352
13. Cagan J., Grossman I.E., Hooker J.N. A conceptual framework for combining artificial intelligence and optimization in engineering design. Research in Engineering Design - Theory, Applications, and Concurrent Engineering, 1997, vol. 9, no. 1, pp. 20–34.
14. Bentley J.L., Olson C., Youngworth R.N. In the era of global optimization, the understanding of aberrations remains the key to designing superior optical systems.
Proceedings of SPIE, 2010, vol. 7849, art. 78490C. doi:
10.1117/12.871720
15. Livshits I.L., Bronchtein I.G., Vasiliev V.N. Information technologies in CAD system for lens design.
Proceedings of SPIE, 2009, vol. 7506, art. 75060C. doi:
10.1117/12.837544
16. Thibault S., Gauvin J., Doucet M., Wang M. Enhanced optical design by distortion control.
Proceedings of SPIE, 2005, vol. 5962, no. 2, art. 596211. doi:
10.1117/12.625151
17. Mack C. Fundamental Principles of Optical Lithography: The Science of Microfabrication. NY, Wiley, 2007, 534 p.
18. Born M., Wolf E. Principles of Optics: Electromagnetic Theory of Propagation, Interference and Diffraction of Light. 7th ed. Cambridge University Press, 1999, 952 p.