Structure and magnetic properties of Fe₂O₃-FeTiO ₃ films

Solid solutions between ilmenite (FeTiO₃) and hematite (α-Fe₂O₃) are one of the candidates for high-temperature magnetic semiconductors. Well-crystallized epitaxial xFeTiO₃-(1-x)Fe₂O₃ (0.5<x<1) films were prepared on both α-Al₂O₃(001) and (110) single-crystalline substrates by reactive sputtering technique. The (110)-oriented films provided more restricted preparation conditions than the (001)-oriented ones. Both films with x<0.7 had large saturation magnetization at room temperature. The magnetic easy plane lay in the (001) crystallographic plane regardless of the film orientations. The magnetic properties of (001)- and (110)-oriented films seemed to be affected not only by the crystalline orientation but also by the lattice strains induced in the films.