CHEMICAL PREPARATION AND CHARACTERIZATION OF TRANSPARENT FERROMAGNETIC Fe:ZnO SEMICONDUCTOR FILMS

摘要

Transparent ferromagnetic semiconductor, Fe_(0.19)Zn_(0.81)O films, were prepared on glass substrates by a novel chemical process involving i) deposition of wurtzite ZnO film on the glass substrate from an aqueous solution and ii) the introduction of Fe impurities into the ZnO film in an aqueous solution. The preparation could be performed by the simple and moderate solutions containing only zinc/iron nitrates and dimetylamine brane (DMAB) at low-temperatures of 323-333 K. The Fe_(0.19)Zn_(0.81)O film exhibited high transparency in the visible light region and room temperature ferromagnetic behavior as well as a semiconducting feature without changes between XRD spectra before and after the Fe-introduction. Soft X-ray magnetic circular dichroism (SXMCD) measurements using synchrotron radiation technique were performed to clarify the origin of room temperature ferromagnetism. The SXMCD results indicated that the incorporated-Fe impurities were found to form non-stoichiometric magnetite with Fe~(III)(A) and Fe~(II)(B) deficients, causing the room temperature ferromagnetism.