Iron oxide magnetic film and process for fabrication thereof
Abstract
Abstract gamma -Fe2O3 film with at least one additive selected from the group consisting of Pd, Au, Pt, Rh, Ag, Ru, Ir, and Os, especially Os are disclosed. Reduction from alpha -Fe2O3 to Fe3O4 is accelerated by additive Os to achieve a uniform reduction and increase the ratio of magnetic phase in the film. gamma -Fe2O3 film medium with Os improved saturation magnetization and increased coercive force in proportion to amount of additive Os. Application of an external field to said film introduces magnetic anisotropy into said film, therefore said film medium improves coercive force and squareness of hysteresis loop by the introduction of anisotropy. gamma -Fe2O3 crystal grain is prepared by additive Os to obtain fine grain. The resultant gamma -Fe2O3 film medium a decreased noise level.
Inventors
- 👤 Osamu Ishii
- 👤 Fumikatsu Yoshimura
- 👤 Iwao Hatakeyama
Bibliographic Details
Claims Analysis
Total Claims: 9References Cited (Backward Citations)
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