Ferromagnetism in Transparent Thin Films of Fe-Doped Indium Tin Oxide

Abstract

Transparent films of Fe-doped indium tin oxide (ITO) were grown at oxygen pressures of 5, 1, 10-1, 10-2, and 10-3 Pa on yttria-stabilized zirconia (001) substrates by a pulsed-laser deposition method. We observed X-ray diffraction peaks from (00h) planes of In2O3 crystalline phase for the films. The films grown at 5 and 1 Pa were paramagnetic and semiconducting, that at 10-1 Pa was ferromagnetic and semiconducting, and those at 10-2 and 10-3 Pa were ferromagnetic and metallic. The Fe-ITO films grown below 10-1 Pa exhibited room-temperature (RT) ferromagnetism. Nanoscale Fe clusters in the highest oxidation state such as γ-Fe2O3 resulted in the RT ferromagnetism.