Full text of article: Russian language.

Abstract:
Two new techniques for solving inverse scatterometry problem for the estimation of trapezoidal diffraction grating parameters are proposed. The techniques are based on designing the polynomial interpolations of different kind for calculation of 0-th diffraction order parameters. The use of polynomial interpolations instead of solving the diffraction problem allows one real-time estimation of grating parameters. Proposed techniques demonstrate high accuracy in the numerical simulations and possess computational efficiency allowing high speed measurements in mass fabrication.

Key words:
diffraction grating, micro- and nanostructures critical dimension measurements, scatterometry.

References:

1. Gereige, I. et al Recognition of diffraction-grating profile using a neural network classifier in optical scatterometry // J. Opt. Soc. Am. A. – 2008. – Vol.25, No.7. – P. 1661-1667.
2. Al-Assaad, R. M., Byrne, D. M. Error analysis in inverse scatterometry. I.-Modeling // J. Opt. Soc. Am. A. – 2007. – Vol.24, No.2. – P. 326-338.
3. Wei, S., Li, L. Measurement of photoresist grating profiles based on multiwavelength scatterometry and artificial neural network // Appl. Opt. – 2008. – Vol.47, No.13. – P. 2524-2532.
4. Abdulhalim, I. Simplified optical scatterometry for periodic nanoarrays in the near-quasi-static limit // Appl. Opt. – 2007. – Vol.46, No.12. – P. 2219-2228.
5. Robert, S., Mure-Ravaud, A., Lacour, D. Characterization of optical diffraction gratings by use of a neural method // J. Opt. Soc. Am. A. – 2002. – Vol. 19 (1). – P. 24-32.
6. Logofatu, P. Scatterometry, an optical metrology technique for lithography / P. Logofatu, D. Apostol, V. Damian, V. Nascov, etc. // Semiconductor Conference, 2004, CAS 2004 Proceedings. – Vol. 2. – P. 517-520
7. Moharam, M. G. Formulation for stable and efficient implementation of the rigorous coupled-wave analysis of binary gratings / M. G. Moharam, E. B. Grann, D. A. Pommet, T. K. Gaylord // J. Opt. Soc. Am. A. – 1995. – Vol.12, No.5. – P. 1068-1076.
8. Doskolovich, L. L., Kadomina, E. A., Kadomin, I. I. Solving scatterometry problem for trapezoidal diffraction gratings // Computer Optics. – 2008. – Vol. 32, No. 1. – P. 29-32. – (in Russian)
9. Johs, B. Optical analysis of complex multilayer structures using multiple data types / B. Johs, R. H. French, F. D. Kalk, W. A. McGahan, J. A. Woollam // Optical Interference coating, Edited by F. Abeles. 1994. – Proc. SPIE, vol. 2253. – P. 1096-1106.
10. Tompkins, H. G., McGahan, W. A. Spectroscopic Ellipsometry and Reflectometry // John Wiley & Sons, Inc. – 1999. – 228 p.
11. Brent, R. P. Algorithms for Minimization Without Derivatives // Prentice–Hall, Englewood Cliffs, NJ. – 1973.
12. Marquardt, D W. An algorithm for least-squares estimation of nonlinear parameters // J. Soc. Indust. Appl. Math. – 1963. – Vol.11. – P. 431-441.
13. Press, W. H. Numerical Recipes in C: The Art of Scientific Computing / W. H. Press, B. P. Flannery, S. A. Teukolsky, W. T. Vetterling // Cambridge University Press. – 1993.
14. Li., L. Use of Fourier series in the analysis of discontinuous periodic structures // J. Opt. Soc. Am. A. – 1996. – Vol.13, No.9. – P. 1870-1876.
15. Peng, S., Morris, G. M. Efficient implementation of rigorous coupled-wave analysis for surface-relief gratings // J. Opt. Soc. Am. A. – 1995. – Vol. 12, No. 5. – P. 1087-1096.
16. Li, L. Fourier modal method for crossed anisotropic gratings with arbitrary permittivity and permeability tensors // J. Opt. A: Pure Appl. Opt. – 2003. – No.5. P. 345-355.
17. Li, L. New formulation of the Fourier modal method for crossed surface-relief gratings // J. Opt. Soc. Am. A. – 1997. – Vol. 14, No. 10. – P. 2758-2767.

---

© 2009, ИСОИ РАН
Россия, 443001, Самара, ул. Молодогвардейская, 151; электронная почта: ko@smr.ru ; тел: +7 (846) 332-56-22, факс: +7 (846 2) 332-56-20