Low Temperature Physics: 35, 79 (2009); https://doi.org/10.1063/1.3064914 (4 pages)
Soft x-ray emission spectra and ferromagnetism in wide-gap doped semiconductors
T.P. Surkova, V.R. Galakhov, and E.Z. Kurmaev
Institute of Metal Physics RAS, Ekaterinburg 620041, Russia
Received Jule 21, 2008
Resonant and non-resonant x-ray emission impurity L spectra in semiconductor compounds ZnS:Mn, ZnO:Mn, ZnO:Co, and Cu2O:Mn have been studied. From the analysis of x-ray emission Mn L2,3 spectra of Zn1–xMnxS (x = 0.1–0.3) it was established that Mn impurities do not form clusters in a ZnS lattice. The study of Mn L2,3 spectra and the electronic structure of epitaxial Zn0.8Mn0.2O film annealed at different temperatures showned that the segregation of Mn atoms in ZnO is the reason of disappearing of ferromagnetic ordering at T > 600 °C. In this case Mn atoms both substitute Zn site, and are in interstitial positions. In the case of Zn1–xCoxO (x = 0.02, 0.06, and 0.10) it was established that the lack of free charge carries is responsible for the absent of exchange interaction between Co ions. X-ray emission Mn L2,3 measurements indicate that in Mn doped Cu2O oxides sintered at 650 °C and 800 °C, Mn atoms are both in interstitial, and aCu substitution positions, but the defect configurations depend on the sintered temperature. A reduction of TC with the increase of the sintered temperature can be explained by the appearance of the antiferromagnetic superexchange between substitutional Mn atoms via oxygen ions.
PACS: 71.55.Gs II–VI Semiconductors;
Key words: x-ray emission spectra, semiconductors, thin films, magnetism.