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Journal of the Optical Society of America A

Journal of the Optical Society of America A


  • Editor: Franco Gori
  • Vol. 27, Iss. 5 — May. 1, 2010
  • pp: 1083–1090

Effective medium approximations for modeling optical reflectance from gratings with rough edges

Brent C. Bergner, Thomas A. Germer, and Thomas J. Suleski  »View Author Affiliations

JOSA A, Vol. 27, Issue 5, pp. 1083-1090 (2010)

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Line edge roughness (LER) has been identified as a potential source of uncertainty in optical scatterometry measurements. Characterizing the effect of LER on optical scatterometry signals is required to assess the uncertainty of the measurement. However, rigorous approaches to modeling the structures that are needed to simulate LER can be computationally expensive. In this work, we compare the effect of LER on scatterometry signals computed using an effective medium approximation (EMA) to those computed with realizations of rough interfaces. We find that for correlation lengths much less than the wavelength but greater than the rms roughness, an anisotropic EMA provides a satisfactory approximation in the cases studied.

© 2010 Optical Society of America

OCIS Codes
(050.1960) Diffraction and gratings : Diffraction theory

ToC Category:
Diffraction and Gratings

Original Manuscript: December 23, 2009
Revised Manuscript: March 8, 2010
Manuscript Accepted: March 8, 2010
Published: April 16, 2010

Brent C. Bergner, Thomas A. Germer, and Thomas J. Suleski, "Effective medium approximations for modeling optical reflectance from gratings with rough edges," J. Opt. Soc. Am. A 27, 1083-1090 (2010)

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