Determination of Optical Constants

The Layer Characterization mode of OptiChar provides a choice of a model from the set of models of a homogeneous thin film. The set includes models the refractive index and extinction coefficient wavelength dependencies:

  • Cauchy model (Normal dispersion)
  • Sellmeier models
  • Model-free refractive index and extinction coefficient
  • Arbitrary Dispersion
  • Exponential model for extinction coefficient (UV-VIS)
  • Hartmann model

You can specify the limits for thin film parameters according to the a priori information about optical properties of the film.

Unique non-parametric models can be used in complicated characterization problems.

Refractive index models
thin film characterization Fitting of experimental reflectance data of SiO2 sample before and after characterization (put the mouse on and out of picture to see changes) thin film characterization Determined refractive index of SiO2 film described by Cauchy model. Determined film thickness is shown on the bottom of the screen.
Our characterization approaches have been carefully verified in the frame of collaboration with the scientists from several world leading research groups. For more detail see our publications:

  1. A. Tikhonravov, M. Trubetskov, T. Amotchkina, G. DeBell, V. Pervak, A. Sytchkova, M. Grilli, and D. Ristau, “Optical parameters of oxide films typically used in optical coating production,” Appl. Opt. 50, C75-C85 (2011).
  2. T. Amotchkina, M. Trubetskov, A. Tikhonravov, V. Janicki, J. Sancho-Parramon, O. Razskazovskaya, and V. Pervak, “Oscillations in spectral behavior of total losses (1 – R – T) in thin dielectric films,” Opt. Express 20, 16129-16144 (2012).
  3. T.V. Amotchkina, V. Janicki, J. Sancho-Parramon, A.V. Tikhonravov, M.K. Trubetskov, and H. Zorc. “General approach to reliable characterization of thin metal films.” Appl. Opt. 50, 10, 1453-1464 (2011).
  4. T.V. Amotchkina, M.K. Trubetskov, A. V. Tikhonravov, V. Janicki, J. Sancho-Parramon, and H. Zorc. “Comparison of two techniques for reliable characterization of thin metal-dielectric films.” Appl. Opt. 50, 6189-6197 (2011).
  5. T. V. Amotchkina, D. Ristau, M. Lappschies, M. Jupe, A. V. Tikhonravov, and M. K. Trubetskov, “Optical Properties of TiO2 -SiO2 Mixture Thin Films Produced by Ion-Beam Sputtering,” in Optical Interference Coatings, OSA Technical Digest (CD) (Optical Society of America, 2007), paper TuA8.
  6. S. Nevas, F. Manoocheri, E. Ikonen, A. V. Tikhonravov, M. A. Kokarev, M. K. Trubetskov, Optical metrology of thin films using high-accuracy spectrophotometric measurements with oblique angles of incidence, Proc. SPIE. 5250, Advances in Optical Thin Films 234 (2004).
  7. A. V. Tikhonravov, M. K. Trubetskov, A. A. Tikhonravov, and A. Duparre’, “Effects of interface roughness on the spectral properties of thin films and multilayers ,” Appl. Opt. 42, 5140-5148 (2003).
  8. A. V. Tikhonravov, M. K. Trubetskov, G. W. DeBell, On the accuracy of optical thin film parameter determination based on spectrophotometric data, Proc. SPIE. 5188, Advanced Characterization Techniques for Optics, Semiconductors, and Nanotechnologies 190 (2003).
  9. A. V. Tikhonravov, M. K. Trubetskov, T. V. Amotchkina, A. A. Tikhonravov, D. Ristau, S. Günster, Reliable determination of wavelength dependence of thin film refractive index, Proc. SPIE. 5188, Advanced Characterization Techniques for Optics, Semiconductors, and Nanotechnologies 331 (2003).
  10. A. V. Tikhonravov, M. K. Trubetskov, M. A. Kokarev, T. V. Amotchkina, A. Duparr, E. Quesnel, D. Ristau, and S. Gunster, “Effect of systematic errors in spectral photometric data on the accuracy of determination of optical parameters of dielectric thin films ,” Appl. Opt. 41, 2555-2560 (2002).
  11. D. Ristau, S. Gunster, S. Bosch, A. Duparre, E. Masetti, J. Ferre-Borrull, G. Kiriakidis, F. Peiro, E. Quesnel, and A. Tikhonravov, “Ultraviolet optical and microstructural properties of MgF2 and LaF3 coatings deposited by ion-beam sputtering and boat and electron-beam evaporation ,” Appl. Opt. 41, 3196-3204 (2002).
  12. A. Tikhonravov, M. K. Trubetskov, A. V. Krasilnikova, E. Masetti, A. Duparre, E. Quesnel, and D. Ristau, “Invesitigation of the surface micro-roughness of fluoride films by spectrometric ellipsometry,” Thin Solid Films 397, 229-237 (2001).
  13. A. V. Tikhonravov, M. K. Trubetskov, E. Masetti, A. V. Krasilnikova, I. V. Kochikov, Sensitivity of the ellipsometric angles psi and delta to the surface inhomogeneity, Proc. SPIE. 3738, Advances in Optical Interference Coatings 173 (1999).
  14. A. V. Tikhonravov, M.K. Trubetskov, G. Clarke, B. T. Sullivan, J. A. Dobrowolski, Ellipsometric study of optical properties and small inhomogeneities of Nb2O5 films, Proc. SPIE. 3738, Advances in Optical Interference Coatings 183 (1999).
  15. A. V. Tikhonravov, M. K. Trubetskov, and A. V. Krasilnikova, “Spectroscopic ellipsometry of slightly inhomogeneous nonabsorbing thin films with arbitrary refractive-index profiles: theoretical study ,” Appl. Opt. 37, 5902-5911 (1998).
  16. A. V. Tikhonravov, M. K. Trubetskov, B. T. Sullivan, and J. A. Dobrowolski, “Influence of small inhomogeneities on the spectral characteristics of single thin films ,” Appl. Opt. 36, 7188-9198 (1997).
  17.  A. V. Tikhonravov, M. K. Trubetskov, Program package for the ellipsometry of inhomogeneous layers, Proc. SPIE. 2046, Inhomogeneous and Quasi-Inhomogeneous Optical Coatings 167 (1993)

Look our video examples

Look our video examples at YouTube

OptiLayer videos are available here:
Overview of Design/Analysis options of OptiLayer and overview of Characterization/Reverse Engineering options.

The videos were presented at the joint Agilent/OptiLayer webinar.