Electronic Transitions and Dispersion Parameters of Annealed TiO2 Films Prepared by Vacuum Evaporation Technique

Autor:	Sami Salmann Chiad, Nabeel A. Bakr, Saad Farhan Oboudi, Nadir F. Habubi
Rok vydání:	2014
Předmět:	Materials science business.industry Annealing (metallurgy) Band gap Optical measurements Analytical chemistry Vacuum evaporation Condensed Matter::Materials Science Wavelength chemistry.chemical_compound chemistry Atomic electron transition Titanium dioxide Optoelectronics Thin film business
Zdroj:	Materials Focus. 3:23-27
ISSN:	2169-429X
DOI:	10.1166/mat.2014.1134
Popis:	Titanium dioxide (TiO2) thin films were successfully grown on glass substrates using vacuum evaporation technique. Optical measurements were studied by UV-VIS technique in the wavelength ranges 300–900 nm. The optical properties and dispersion parameters of the films have been studied as a function of annealing temperature, results show that the annealing temperature has a significant effect on the transparency of the thin films. The optical energy gap decreased from 3.25 to 2.95 eV as the annealing temperature increases to 250 � C. The density of localized states increased by this process and causes an expanding in the Urbach tail and consequently decreases the energy gap. The changes in dispersion parameters and Urbach tails were investigated. The single-oscillator parameters have been reported.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::e524687b613ebf01e03358121e22b7bf https://doi.org/10.1166/mat.2014.1134 Zobrazit plný text záznamu