TY - JOUR
T1 - An approach for measuring the ellipsometric parameters of isotropic and anisotropic thin films using the stokes parameter method
AU - Lo, Yu Lung
AU - Hsieh, Wen Hsiang
AU - Chung, Yi Fan
AU - Tsai, Shiou An
N1 - Funding Information:
Manuscript received December 15, 2011; revised March 09, 2012; accepted April 22, 2012. Date of current version May 23, 2012. This work was supported in part by the National Science Council of Taiwan under Grant NSC99-2221-E-006-034-MY3.
PY - 2012
Y1 - 2012
N2 - A method is proposed for extracting the ellipsometric parameters of isotropic and anisotropic thin films from the Stokes parameters obtained for five different input polarization lights, namely four linearly polarized lights and one right-hand circular polarized light. In the proposed approach, the genetic algorithm in curve fitting is used to extract the refractive index and thickness properties of the isotropic or anisotropic sample from the experimental results obtained for the variation of the ellipsometric parameters with the incident angle. Finally, the experimental values of the ellipsometric parameters and the simulated values are compared. It is shown that for a typical isotropic thin film, the average standard deviations of Ψ pp and Δ pp are 0.020 ° and 0.464 °, respectively. Meanwhile, for a typical anisotropic thin film, the average standard deviations of Ψ pp, Ψ ps, Ψ sp, Δ pp, Δ ps, and Δ sp are found to be 0.014 °, 0.047 °, 0.041 °, 0.312 °, 0.402 °, and 0.571 °, respectively. Overall, the results presented in this study confirm that the proposed method provides a straightforward and reliable means of extracting the ellipsometric parameters of isotropic and anisotropic materials by Stokes parameters using five independent input polarization lights. Specially, the ellipsometric parameters of anisotropic thin film expressed by Stokes parameters or Mueller elements are explicitly presented.
AB - A method is proposed for extracting the ellipsometric parameters of isotropic and anisotropic thin films from the Stokes parameters obtained for five different input polarization lights, namely four linearly polarized lights and one right-hand circular polarized light. In the proposed approach, the genetic algorithm in curve fitting is used to extract the refractive index and thickness properties of the isotropic or anisotropic sample from the experimental results obtained for the variation of the ellipsometric parameters with the incident angle. Finally, the experimental values of the ellipsometric parameters and the simulated values are compared. It is shown that for a typical isotropic thin film, the average standard deviations of Ψ pp and Δ pp are 0.020 ° and 0.464 °, respectively. Meanwhile, for a typical anisotropic thin film, the average standard deviations of Ψ pp, Ψ ps, Ψ sp, Δ pp, Δ ps, and Δ sp are found to be 0.014 °, 0.047 °, 0.041 °, 0.312 °, 0.402 °, and 0.571 °, respectively. Overall, the results presented in this study confirm that the proposed method provides a straightforward and reliable means of extracting the ellipsometric parameters of isotropic and anisotropic materials by Stokes parameters using five independent input polarization lights. Specially, the ellipsometric parameters of anisotropic thin film expressed by Stokes parameters or Mueller elements are explicitly presented.
UR - http://www.scopus.com/inward/record.url?scp=84861838019&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84861838019&partnerID=8YFLogxK
U2 - 10.1109/JLT.2012.2196977
DO - 10.1109/JLT.2012.2196977
M3 - Article
AN - SCOPUS:84861838019
VL - 30
SP - 2299
EP - 2306
JO - Journal of Lightwave Technology
JF - Journal of Lightwave Technology
SN - 0733-8724
IS - 14
M1 - 6205398
ER -