We have succeeded in fabricating of hematite (α-Fe2O3) antiferromagnetic (AF) thin films by the ion beam sputtering method, which give unidirectional anisotoropy to the adjacent ferromagnetic layer. Its exchange bias energy (Jex) is 0.03 erg/cm2, and blocking temperature (Tb) is 250°C. Spin-valve films with the hematite AF layer were also fabricated. They exhibit GMR property with unidirectional anisotoropy of the pinned layer. Spin- valve films of which magnetic layers consist of only NiFe exhibit relatively low MR ratio and poor thermal stability. However, the spin-valve using Co as the pinned layer and the free layer at the Cu interface exhibits MR ratio of more than 6 % and excellent thermal stability.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Electrical and Electronic Engineering