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

摘要

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 In_2O_3 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-Fe_2O_3 resulted in the RT ferromagnetism.