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Al and Ti doped ZnO thin films have been prepared by direct current magnetron cosputtering and thermal oxidation. The effects of these dopants on the microstructural, morphological and electrical properties of deposited films have been studied. The SEM demonstrated that the undoped ZnO thin film consisted of globular ZnO with particle size of ∼100 nm. Scanning electron microscopy EDX analysis confirmed that the dopant content in the ZnO–Al and ZnO–Ti thin film was 2·78 and 3·75 at-% respectively. The particle in the ZnO–Ti thin film was blocky or granular with thorns and its size was several micrometers, while the particle in ZnO–Al thin film was porous granular and the size was ∼2 μm. Resistance value testing and R/R calculation revealed that pure ZnO thin film had the highest gas sensitivity. [ABSTRACT FROM AUTHOR]

Strontium titanate films were grown by standard and interval pulsed laser interval deposition on (001) strontium titanate and magnesium oxide substrates. Reflection high-energy electron diffraction (RHEED) was used to monitor the growth mode of the films. The microstructures were investigated using transmission electron microscopy. The temporal evolution of the RHEED intensity confirmed a layer-by-layer growth mode in the homoepitaxial case. In heteroepitaxy, three dimensional growth occurred. Misfit dislocations and threading dislocations were the dominant defects. The film grown using the standard deposition was relaxed; the film grown using interval deposition was under in-plane tension and showed fewer threading dislocations. [ABSTRACT FROM AUTHOR]