Structural and Optical properties investigations of pristine and Strontium-doped ZnO synthesized via pulse laser deposition

Document Type : Original Research Paper

Authors

1 1. Department of Physics Education, Farhangian University, P.O. Box 14665-889, Tehran, Iran

2 Department of Physics, Faculty of Science, Malayer University, Malayer, Iran.

10.22111/cnmst.2025.50508.1256

Abstract

Undoped and Strontium doped ZnO thin films were deposited by pulse laser deposition whose average crystallite size lies within the range of 38–53 nm. The deposited film's structure showed that the films crystallized in hexagonal wurtzite structure. The band gap was originating to be 3.31 and 3.20 eV for undoped ZnO and Sr doped ZnO thin films, respectively due to the lattice distortion and creation of active imperfections in the ZnO lattice. The photoluminescence emissions confirmed the presence of defects related to oxygen vacancies and zinc interstitials. SEM images revealed plate-like morphology with hexagonal shape regardless of the sizes. The sensing results revealed that ZnO doped 3% Strontium exhibited the highest response, achieving 41 % at 50 ppm ethanol at an operating temperature of 352 °C. The electrical sheet resistance per square area of undoped ZnO and Sr doped ZnO thin films was obtained to be 4.5×10^(+7) Ω/sq and 7.0×10^(+7) Ω/sq, respectively. ZnO thin films have been studied extensively for electronics and optoelectronic applications..

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