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Nanoscience & Nanotechnology-Asia


ISSN (Print): 2210-6812
ISSN (Online): 2210-6820

Research Article

Optical Characterization of Al-doped ZnO Films via Sol-gel Method Using Spectroscopic Ellipsometry

Author(s): Ehsan M. Aghkonbad, Hassan Sedghi* and Maryam M. Aghgonbad

Volume 10 , Issue 5 , 2020

Page: [642 - 648] Pages: 7

DOI: 10.2174/2210681209666190328221704

Price: $65


Background: Al-doped ZnO thin films are considered as a promising alternative to ITO in optoelectronic applications. In this work, Al-doped ZnO thin films were prepared using sol-gel spin coating technique.

Experimental: The optical properties of the films such as refractive index, extinction coefficient, dielectric function and the absorption coefficient were examined using spectroscopic ellipsometry method in the wavelength range of 300 to 900 nm. The effect of Al doping on ZnO thin films with different Al concentrations was significant. Tauc relation was used to estimate the optical band gap energy of the films.

Results: The calculated values of band gap energy were obtained between 3.10 to 3.25 eV. Also the fraction of voids was calculated using Aspnes theory.

Conclusion: The free carrier concentration value was obtained in the order of 1019 cm-3.

Keywords: Al doping, spectroscopic ellipsometry, ZnO thin film, band gap energy, semiconductors, polarization state.

Graphical Abstract
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