Actas de congresos
Estimation Of Optical Parameters Of Very Thin Films
Registro en:
Applied Numerical Mathematics. , v. 47, n. 2, p. 109 - 119, 2003.
1689274
10.1016/S0168-9274(03)00055-2
2-s2.0-0141924678
Autor
Birgin E.G.
Chambouleyron I.E.
Martinez J.M.
Ventura S.D.
Institución
Resumen
In recent papers, the problem of estimating the thickness and the optical constants (refractive index and absorption coefficient) of thin films using only transmittance data has been addressed by means of optimization techniques. Models were proposed for solving this problem using linearly constrained optimization and unconstrained optimization. However, the optical parameters of "very thin" films could not be recovered with methods that are successful in other situations. Here we introduce an optimization technique that seems to be efficient for recovering the parameters of very thin films. © 2003 IMACS. Published by Elsevier B.V. All rights reserved. 47 2 109 119 Birgin, E.G., Chambouleyron, I., Martínez, J.M., Estimation of the optical constants and the thickness of thin films using unconstrained optimization (1999) J. Comput. Phys., 151, pp. 862-880 Chambouleyron, I.E., Martínez, J.M., Moretti, A.C., Mulato, M., Optical constants of thin films by means of a pointwise constrained optimization approach (1998) Thin Solid Films, 317, pp. 133-136 Chambouleyron, I.E., Martínez, J.M., Moretti, A.C., Mulato, M., The retrieval of the optical constants and the thickness of thin films from transmission spectra (1997) Appl. Optics, 36, pp. 8238-8247 Friedlander, A., Martínez, J.M., Santos, S.A., A new trust region algorithm for bound constrained minimization (1994) Appl. Math. Optimization, 30, pp. 235-266 http://www.ime.unicamp.br/~martinezMulato, M., Chambouleyron, I., Birgin, E.G., Martínez, J.M., Determination of thickness and optical constants of amorphous silicon films from transmittance data (2000) Appl. Phys. Lett., 77, pp. 2133-2135 Raydan, M., The Barzilai and Borwein gradient method for the large unconstrained minimization problem (1997) SIAM J. Optim., 7, pp. 26-33 Swanepoel, R., Determination of the thickness and optical constants of amorphous silicon (1983) J. Phys. E: Sci. Instrum., 16, pp. 1214-1222 Wemple, S.H., Refractive-index behavior of amorphous semiconductors and glasses (1973) Phys. Rev. B, 7, pp. 3767-3777