We prepared κ-Al2O3-type structured AlxFe2-xO3 films in the range of x = 0 - 1.70 deposited on SrTiO3(111) substrates and investigated their crystal structures and magnetic properties. All films could be stabilized in the κ-Al2O3-type orthorhombic phase, and the lattice parameters were found to be monotonically decreased with an increase in the Al content. Néel temperature of AlxFe2-xO3 films was found to decrease with an increase in Al content, until the Al1.70Fe0.30O3 film showed paramagnetic behavior. On the other hand, saturation magnetization showed a maximum 0.79 μB/Fe at 10 K in the Al0.91Fe1.09O3 film, manifesting the preferential occupation of Al in the tetrahedral site. Cross sectional TEM observation has revealed the columnar growth of AlxFe2-xO3 films with an average width of ∼10 nm on the bottom layer that may have a similar cation arrangement with a bixbyite-type structure.
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