Multi-objective genetic algorithm applied to spectroscopic ellipsometry of organic-inorganic hybrid planar waveguides

Abstract

Abstract:The applicably of multi-objective optimization to ellipsometric data analysis is presented and a method to handle complex ellipsometric problems such as multi sample or multi angle analysis using multi-objective optimization is described. The performance of a multi-objective genetic algorithm (MOGA) is tested against a single objective common genetic algorithm (CGA). The procedure is applied to the characterization (refractive index and thickness) of planar waveguides intended for the production of optical components prepared sol-gel derived organicinorganic hybrids, so-called di-ureasils, modified with zirconium tetrapropoxide, Zr(OPr n ) 4 deposited on silica on silicon substrates. The results show that for the same initial conditions, MOGA performs better than the CGA, showing a higher success rate in the task of finding the best final solution. ©2010 Optical Society of America

Refractive index characterization of waveguide channels using spectroscopic ellipsometry

“…The MOGA produces results with a distance to the final solution smaller than the ones arising from the CGA and with lower dispersion. These results are in accordance with those reported in the study of the refractive index and thickness of di-ureasil planar waveguides [5].…”

“…Di-ureasil organic-inorganic hybrids were prepared using a synthetic procedure previously described in detail [5]. The diureasil organic-inorganic host was doped with 40% molar of ZrOMc with Zr(OPr n ) 4 :McOH molar ratio of 1:1.…”

“…The solutions which are non-dominated by any other belong to the so called Pareto set. The application of this concept to some problems in ellipsometry was shown to be beneficial [5].…”

Advancing x-ray scattering metrology using inverse genetic algorithms

“…Additionally, a series of objective functions are investigated for each algorithm to see how the high dynamic range of scattering intensity measurements affects convergence of model parameters. Similar high dynamic range data is encountered in other problems where inverse solutions are needed such as X-ray or neutron reflectivity 48 , ellipsometry 49,50 , scatterometry/OCD metrology 51 , or seismic surveying 52,53 , thus the methods presented should be applicable in those fields as well. The results of these various runs are compared to infer which algorithm and objective function combination is best suited for optimized fitting of scattering data in terms of both refinement speed and convergence robustness.…”

Optical Fiber Relative Humidity Sensor Based on a FBG with a Di-Ureasil Coating

“…The di-ureasil, termed as d-U(600), was prepared using a procedure described in detailed elsewhere [46,47]. For the precursor synthesis, a tetrahydrofuran (THF, Riedel-de Haën) solution containing isocyanate-propyl-trietoxisilane (ICPTES, Aldrich) and a diamine commercially known as Jeffamine 600 ® (Aldrich) is introduced into a reflux system, with a molar ratio Jeffamine 600 ® :ICPTES of 2:1 at 82 °C for 18 h, under magnetic stirring.…”