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Three different techniques, natural oxidation, remote plasma oxidation and low energy ion beam oxidation, have been proved to be equally effective in forming nano-oxide layers (NOLs) in spin-valve films for specular enhancement of giant magnetoresistance (GMR) effect. GMR values over 12% have been routinely obtained in spin-valve films with NOL, corresponding to a 30% specular enhancement over those without NOL. The consistency and robustness of the oxidation processes has been demonstrated by a very large GMR value ∼19% in a dual spin-valve film with the NOLs formed in both pinned layers, the oscillatory dependence of the interlayer coupling field on Cu layer thickness in specular enhanced spin-valve films and the uniform and repeatable film performance over 5 in. substrates. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

We clarify the origin of the interface perpendicular magnetic anisotropy (PMA) at the Cr2O3/ferromagnet interface by investigating the temperature dependence of the magnetic properties of Cr2O3/Co-Pt. We observed positive large interface PMA both above and below the blocking temperature of Cr2O3, with the PMA being less sensitive to temperature. Our results indicate that the effect of the metal/oxide interface, as well as that of the MgO/CoFeB interface, contributes strongly to the PMA at the Cr2O3/Co-Pt interface, although the effect of perpendicular exchange coupling might also slightly contribute to the interface PMA. [ABSTRACT FROM AUTHOR]

We investigate the magnetic, electric, and magnetoelectric properties of a Cr2O3 thin film system that was deposited by radiofrequency magnetron sputtering. The temperature dependence of the magnetic susceptibility of our Cr2O3 film is similar to that of bulk Cr2O3, which indicates a small oxygen non-stoichiometry in the film. The Cr2O3 film exhibits high AC resistivity (∼109 Ωcm) and low leakage current (4.0×10-5 A/cm2 at E=80 kV/cm). Finally, we demonstrate magnetoelectric switching of the exchange bias using the Cr2O3/Pt/Co all-thin-film system. By changing the direction of the electric field during the magnetoelectric field cooling process, the exchange bias field was changed symmetrically from -160 Oe to +160 Oe, which represents the switching of the antiferromagnetic domain of Cr2O3. [ABSTRACT FROM AUTHOR]

Presents a study on annealing time and temperature dependences of magnetoresistive (MR) ratio in CoFe/Cu spin-valves. Experimental procedures; Results; Conclusion.