## Interferometric Characterization of Subwavelength Lamellar Gratings

Applied Optics, Vol. 38, Issue 23, pp. 4980-4984 (1999)

http://dx.doi.org/10.1364/AO.38.004980

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### Abstract

We propose a new, to our knowledge, method for determining the two main critical parameters of periodic one-dimensional lamellar structures, namely, linewidths and etched depths. The method is simple and requires only two measurements for the phase of the zero-transmitted order under two orthogonal polarizations. It is inspired by the analogy between subwavelength gratings and anisotropic homogeneous thin films. The method is tested with experimental data obtained with a Mach–Zehnder interferometer. Etched depths and linewidths derived from the interferograms and electromagnetic theory are compared with scanning-electron-microscope observations.

© 1999 Optical Society of America

**OCIS Codes**

(050.1380) Diffraction and gratings : Binary optics

(050.1950) Diffraction and gratings : Diffraction gratings

(050.1970) Diffraction and gratings : Diffractive optics

(290.3200) Scattering : Inverse scattering

**Citation**

Philippe Lalanne, P. Pichon, P. Chavel, E. Cambril, and H. Launois, "Interferometric Characterization of Subwavelength Lamellar Gratings," Appl. Opt. **38**, 4980-4984 (1999)

http://www.opticsinfobase.org/ao/abstract.cfm?URI=ao-38-23-4980

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### References

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