Enhanced physical characteristics of ZnO thin films through Sr and Mg co-doping

ABSTRACT

In this study, undoped ZnO, (Sr, Mg) co-doped ZnO (SMZO) thin films were synthetised on heated glass substrates at a temperature of 250°C by using ultrasonic spray technique. Doping strontium (Sr) and magnesium (Mg) into zinc oxide (ZnO) offers an important way to modify various properties. X-ray diffraction (XRD) confirmed that the films exhibited the hexagonal wurtzite structure of ZnO with a favored orientation along (002) plane . Scanning electron microscope (SEM) showed a strong change in the surface morphology while Energy dispersive X-ray spectrometer (EDX) and mapping confirmed the purity of the films . UV-Visible studies demonstrated that the optical transmittance was improved to an average value above 94% and that Mg-doping induces an increase of the band gap indicating high optical quality of the films. From the fabricated films, SMZO3 is the most appropriate for optoelectronic applications where a low resistivity and high figure of merit were obtained.

KEYWORDS:

• ZnO
• SZO
• SMZO
• thin films
• ultrasonic spray
• band gap
• hall effect

Acknowledgments

The authors acknowledge the Centre National pour la Recherche Scientifique et Technique (CNRST), Rabat, Morocco for providing financial support to this work under the Research Excellence Scholarships Program (No. 12UM5R2018).

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the Centre national pour la recherche scientifique et technique (CNRST) Rabat, Morocco [No. 12UM5R2018].