Critical-point model dielectric function analysis of WO3 thin films deposited by atomic layer deposition techniques

Authors

Ufuk Kılıç, University of Nebraska-LincolnFollow
Derek Sekora, University of Nebraska-LincolnFollow
Alyssa Mock, University of Nebraska-LincolnFollow
Rafał Korlacki, University of Nebraska-LincolnFollow
Elena M. Echeverría, University of Nebraska-LincolnFollow
Natale J. Ianno, University of Nebraska-LincolnFollow
Eva Schubert, University of Nebraska-LincolnFollow
Mathias Schubert, University of Nebraska-LincolnFollow

Document Type

Article

Date of this Version

5-2018

Citation

arXiv:1805.04171v1 [ cond-mat.mtrl-sci] 8 May 2018

Comments

Copyright (c) 2018 Ufuk Kılıç, Derek Sekora, Alyssa Mock, Rafał Korlacki, Elena M. Echeverría, Natale Ianno, Eva Schubert, and Mathias Schubert

Abstract

WO₃ thin films were grown by atomic layer deposition and spectroscopic ellipsometry data gathered in the photon energy range of 0.72-8.5 eV and from multiple samples was utilized to determine the frequency dependent complex-valued isotropic dielectric function for WO₃. We employ a critical-point model dielectric function analysis and determine a parameterized set of oscillators and compare the observed critical-point contributions with the vertical transition energy distribution found within the band structure of WO₃ calculated by density functional theory. We investigate surface roughness with atomic force microscopy and compare to ellipsometric determined effective roughness layer thickness.