Temperature dependent optical properties of ZnO thin film using ellipsometry and photoluminescence
| Autor: | M.-A. Zaïbi, M.-B. Bouzourâa, Stéphane Dalmasso, A. En Naciri, Meherzi Oueslati, Yann Battie |
|---|---|
| Přispěvatelé: | Laboratoire de Chimie et Physique - Approche Multi-échelle des Milieux Complexes (LCP-A2MC), Université de Lorraine (UL), Laboratoire LANSER, Université de Tunis El Manar (UTM), Université de Tunis, Ecole Nationale Supérieure des Ingénieurs de Tunis |
| Rok vydání: | 2018 |
| Předmět: |
[PHYS]Physics [physics]
010302 applied physics Quenching Spin coating Photoluminescence Materials science Condensed matter physics Condensed Matter::Other Exciton 02 engineering and technology Atmospheric temperature range 021001 nanoscience & nanotechnology Condensed Matter Physics 01 natural sciences Molecular electronic transition Condensed Matter::Materials Science Ellipsometry 0103 physical sciences General Materials Science Electrical and Electronic Engineering Thin film 0210 nano-technology ComputingMilieux_MISCELLANEOUS |
| Zdroj: | Superlattices and Microstructures Superlattices and Microstructures, Elsevier, 2018, 117, pp.457-468. ⟨10.1016/j.spmi.2018.03.078⟩ |
| ISSN: | 0749-6036 1096-3677 |
| DOI: | 10.1016/j.spmi.2018.03.078 |
| Popis: | We report the temperature dependence of the dielectric function, the exciton binding energy and the electronic transitions of crystallized ZnO thin film using spectroscopic ellipsometry (SE) and photoluminescence (PL). ZnO layers were prepared by sol-gel method and deposited on crystalline silicon (Si) by spin coating technique. The ZnO optical properties were determined between 300 K and 620 K. Rigorous study of optical responses was achieved in order to demonstrate the quenching exciton of ZnO as a function of temperature. Numerical technique named constrained cubic splines approximation (CCS), Tauc-Lorentz (TL) and Tanguy dispersion models were selected for the ellipsometry data modeling in order to obtain the dielectric function of ZnO. The results reveals that the exciton bound becomes widely flattening at 470 K on the one hand, and on the other that the Tanguy dispersion law is more appropriate for determining the optical responses of ZnO thin film in the temperature range of 300 K–420 K. The Tauc-Lorentz, for its part, reproduces correctly the ZnO dielectric function in 470 K–620 K temperature range. The temperature dependence of the electronic transition given by SE and PL shows that the exciton quenching was observed in 420 K–∼520 K temperature range. This quenching effect can be explained by the equilibrium between the Coulomb force of exciton and its kinetic energy in the film. The kinetic energy was found to induce three degrees of freedom of the exciton. |
| Databáze: | OpenAIRE |
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