Abstract
A method for the evaluation of experimental data from spectroscopic ellipsometry is proposed which combines the global-search optimization algorithm with statistical model selection criteria. The hybrid genetic-gradient search algorithm (HGGA) is applied to find the optical parameters and thickness of a diamond-like carbon (DLC) coating deposited on SW7M stainless steel. Akaike and Bayesian information criteria are used to evaluate the different dielectric function models. The method is able to find optical model parameters even in case of a limited initial knowledge about the material optical constants. At the same time, the optimal dielectric function model for the description of the material optical properties can be selected unambiguously from the set of candidate models.
Funding source: Narodowe Centrum Nauki
Award Identifier / Grant number: 2018/02/X/ST5/02508
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Author contributions: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.
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Research funding: K. Dorywalski gratefully acknowledge the funding by the National Science Centre, Poland, under grant no. 2018/02/X/ST5/02508.
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Conflict of interest statement: The authors declare no conflicts of interest regarding this article.
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Articles in the same Issue
- Frontmatter
- Editorial
- Making impact
- Community
- EOS annual meeting EOSAM 2022
- Topical Issue: Ellipsometry Part 2; Guest Editors: Rüdiger Schmidt-Grund, Chris Sturm and Andreas Hertwig
- Review Article
- Polarimetric techniques for the structural studies and diagnosis of brain
- Research Articles
- Combination of a global-search method with model selection criteria for the ellipsometric data evaluation of DLC coatings
- Ellipsometry study of the infrared-active phonon modes in strained SrMnO3 thin films
- Research Articles
- A generalised thermal LED-model and its applications
- Novel procedure for the identification of a starting point for the CMP