The Effect of Mg Content on the Physical Properties of ZnO Films Deposited by Ultrasonic Spray Pyrolysis

Abstract

ZnO is a versatile material and tailoring its physical properties to the field of application is technologically crucial. Intentionally doping with a foreign element is the most common and useful method for that. In this presented work, ZnO films doped at different Mg concentrations (0%, 5%, 10%, and 15%) were deposited onto glass substrates by ultrasonic spray pyrolysis in order to investigate the effect of Mg doping. AFM and SEM images captured for the morphological investigations revealed that Mg doping deteriorated the surface of the films. The structural analysis showed that the Mg doping at 5% enhanced the structural properties, but the crystallization level was adversely affected at higher Mg concentrations. Optical band gap and Urbach energies increased from 3.30 eV to 3.45 eV and from 79.5 meV to 119.8 meV, respectively. The lowest electrical resistivity was noted as 8.72101 cm for Mg-doped ZnO films at 5%.

Keywords

• Ultrasonic spray pyrolysis
• Mg doping
• ZnO thin films
• optical properties

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