INFLUENCE OF ALUMINUM CONCENTRATION ON THE ELECTRICAL AND OPTICAL PROPERTIES OF ZnO THIN FILMS

Year 2016, Volume: 3 Issue: 3, 453 - 462, 08.01.2017

Ebru Güngör Tayyar Gungor

https://doi.org/10.18596/jotcsa.18812

Cited By: 2

Abstract

Al:ZnO thin films having with different Al concentrations were deposited on glass substrates by a sol-gel technique. The effects of Al doping on the structural, optical and electrical properties of Al:ZnO were investigated using with XRD, optical transmittance and sheet resistance measurements. The concentration of zinc acetate was 0.1 M. Al content in the starting solution was varied from 0 to 20% as the molarity range. Optical transmittance spectra of the films in the form of Film/Glass were used to determine the film thickness and optical band gaps. The optical transmissions of Al:ZnO thin films were higher than 80% in the visible and near infrared region. The optical band gaps of Al:ZnO films decrease with increase of Al content. In order to obtain the average sheet resistance of the films the current and voltage through the probes have been measured for five different position by four-point probe method. The results showed that the sheet resistances of Al:ZnO thin films increased with the Al concentration. Considering the film thickness and geometric factor, the electrical resistivity values were computed. It was observed that the sheet resistance of AZO films up to 10% molarity of Al in the starting solution increased.

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