Semimagnetic semiconductor oxides as materials for transparent electronics and spintronics

Abstract

Zinc oxide-based semimagnetic semiconductor (SMS) ZnMnO, ZnMnFeO and ZnMnSnO thin films were deposited on sapphire and glass substrate by pulsed laser deposition (PLD) and RF sputtering techniques. Further, ZnMnO nanocrystals embedded in polyvinyl alcohol (PVA) and polyvinyl pyrrolidone (PVP) matrices were prepared by chemical method employing zinc acetate and manganese acetate as precursors. The morphology of the thin films was studied using atomic force microscopy (AFM). Large variety of the morphology images was obtained depending on the film composition and growth conditions. The most interesting feature was observed for the ZnMnSnO films, in which the formation of clusters including nanowire-like structures was shown. Optical transmission spectra suggest that metalsMn, Fe and Sn substitute for Zn2+ ions in the ZnO lattice, resulting in the increase in the band gap energy.Magneto-optical Faraday rotation measurements confirm ferromagnetic ordering in ZnMnFeO thin films and paramagnetic behaviour for the other films.