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Optical analysis of room temperature magnetron sputtered ITO films by reflectometry and spectroscopic ellipsometry

Published online by Cambridge University Press:  28 July 2014

Tivadar Lohner*
Affiliation:
Department of Photonics, Research Centre for Natural Sciences, Institute for Technical Physics and Materials Science, H-1121 Budapest, Hungary
K. Jagadeesh Kumar
Affiliation:
Semiconductor Laboratory, Department of Physics, Indian Institute of Technology Madras, Chennai 600036, India
Péter Petrik
Affiliation:
Department of Photonics, Research Centre for Natural Sciences, Institute for Technical Physics and Materials Science, H-1121 Budapest, Hungary; and Department of Nanotechnology, University of Pannonia, H-8200 Veszprém, Hungary
Aryasomayajula Subrahmanyam
Affiliation:
Semiconductor Laboratory, Department of Physics, Indian Institute of Technology Madras, Chennai 600036, India
István Bársony
Affiliation:
Research Centre for Natural Sciences, Institute for Technical Physics and Materials Science, H-1121 Budapest, Hungary; and Department of Nanotechnology, University of Pannonia, H-8200 Veszprém, Hungary
*
a)Address all correspondence to this author. e-mail: [email protected]
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Abstract

Indium-tin-oxide (ITO) thin films were prepared by reactive magnetron sputtering; their optical constants and thickness were determined by spectral reflectometry (SR) in the wavelength range from 400 nm to 800 nm and spectroscopic ellipsometry (SE) in the wavelength range from 191 nm to 1690 nm. A comparative evaluation of the measured data from SR and SE has been made using the same single layer optical model based on the Cauchy dispersion relation. The introduction of a surface roughness layer into the optical model considerably improved the fit quality during evaluation of SE data. Vertical inhomogeneity of the ITO thin films was assessed using a multilayer optical model describing porosity gradient and the three-layer optical model suggested by Jung [Y.S. Jung, Thin Solid Films467, 36 (2004)] from the SE data.

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Copyright
Copyright © Materials Research Society 2014 

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References

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