ZnO nanostructured thin films: Depositions, properties and applications-A review

The present review focuses on the growth, properties and applications of ZnO thin films grown by various physical deposition techniques. An overview on several deposition methods such as thermal evaporation, arc deposition, pulse laser deposition and sputtering for the growth of ZnO thin films are discussed in this review. Several factors such as substrate temperature, gas pressures, oxygen partial pressures, and post growth annealing temperatures which influence the properties of ZnO thin films are also discussed. Various ZnO thin film properties such as surface morphologies, surface film thickness, grain size, optical transmittance, sensitivity, electrical conductivity, uniformity and electrical resistivity are presented in this review. In addition, numerous applications of ZnO thin films, for instance, thin film based gas sensors, surface acoustic wave (SAW) devices; thin film transistors (TFTs), light emitting diodes (LEDs) and solar cells are discussed.