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In this paper we report the results on the fabrication of diluted magnetic semiconductors Zn 1−x Mn x O 1−y S y thin films with manganese x = 0.05 and sulfur 0 ≤ y ≤ 0.15 compositions, respectively, by using ultrasonic spray pyrolysis method. The influence of the sulfur concentration on the band gap energy, structural and magnetic properties have been studied by using optical transmission, X-ray diffraction and superconducting quantum interference device (SQUID) measurements, respectively. The morphology and composition of samples were studied by using Scanning Electron Microscope (SEM) and X-ray photoelectron spectroscopy (XPS). With increasing of the sulfur concentration the band gap energy of composition decreases, while the magnetization increases proportional to the sulfur concentration. [ABSTRACT FROM AUTHOR]

Optical and resistance switching properties in the Ag/ZnO/Pt structure were investigated. Two types of resistance switching (bipolar and monopolar) were observed. Photoluminescence measurements showed dissimilar emission spectra for the each type of switching that might be explained by different processes occurred during resistance switching. In case of the bipolar resistance switching, the change in the ultraviolet part of spectrum was observed and it was attributed to Ag+ ions migration. On the other hand, the monopolar switching demonstrated the changes in the visible luminescence emission that could be, in turn, interpreted by the generation/recovery of oxygen vacancies. [ABSTRACT FROM AUTHOR]

The article discusses the use of ultrasound-spraying method in determining the electrophysical and optical properties of thin zinc oxide (ZnO) films. Zinc oxide is a direct-gap semiconductor and a promising material from the basis of the fabrication of visible-radiation sources operating in blue spectral regions. The mechanism of the acceptor doping and the effect of the specific resistance of silicon substrates on the properties of thin ZnO is examined using the method.

ZnO nanorods doped with 1–2 wt% Cr were grown on Si substrates by hydrothermal method. Scanning electron spectroscopy and X-ray diffraction show the hexagonal structure of the nanorods with ZnO oriented along (1 0 0), (0 0 2), (1 0 1) and (1 0 2) and CrO 2 along (2 1 1). Ionized donor bound exciton, neutral donor bound exciton, free exciton, two-electron-satellite of hydrogen donor bound exciton, and donor acceptor pairs were observed in low temperature photoluminescence spectra. The photoluminescence spectra along with XPS results confirm that Zn i was formed in the low temperature hydrothermal process. Superconducting quantum interference device measurement reveals that the Cr-doped ZnO nanorods are ferromagnetic with saturation magnetization of 2.421 × 10 −3 emu/g. The room temperature ferromagnetic properties are explained by defect-mediated bound magnetic polarons based on Zn i. [ABSTRACT FROM AUTHOR]