Nec Corporation

Jun-Ichi Fujikata

Kazuhiko Hayashi

Kunihiko Ishihara

Hidefumi Yamamoto

Masafumi Nakada

Nobuyuki Ishiwata

Keishi Ohashi

Tsutomu Ishi

Atsushi Kamijo

Hisanao Tsuge

Hisao Matsutera

Hiroaki Honjou

In a magnetoresistive effect transducer including a pinning layer, a pinned layer, a free layer and a non-magnetic layer inserted between the pinned layer and the free layer, a longitudinal bias layer is connected directly to a part of the free layer to apply a bias magnetic field to the free layer, thus biasing a magnetization direction of the free layer so that the magnetization direction of the free layer coincides with that of the longitudinal bias layer.

Magnetoresistive effect transducer having longitudinal bias layer and control layer directly connected to free layer

Magnetoresistive effect transducer having longitudinal bias layer directly connected to free layer

In a magnetoresistive element, an underlying metal layer is formed on a substrate, and a magnetoresistive layer is formed on the underlying metal layer. The underlying metal layer has a thickness of about 0.1 to 3.0 nm.

Magnetoresistive effect element having magnetoresistive layer and

The invention provides a magnetoresistance effects film including (a) at least two thin magnetic films deposited on a substrate, (b) at least one thin nonmagnetic film interposed between the thin magnetic films, and (c) a thin antiferromagnetic film disposed adjacent to one of the thin magnetic films between which the thin nonmagnetic film is interposed. A bias magnetic field of one of the thin magnetic films induced by the thin antiferromagnetic film has an intensity Hr greater than a coercivity H.sub.C2 of the other of the thin magnetic films which is remote from the thin antiferromagnetic film (Hr&gt;H.sub.C2). The thin antiferromagnetic film has a superlattice structure composed of at least two of NiO, Ni.sub.x Co.sub.1-x O(x=0.1-0.9) and CoO. A ratio of Ni relative to Co in the number of atoms in the superlattice structure is set equal to or greater than 1.0. The magnetoresistance effects film exhibits large linear change in resistance with the hysteresis being small even when a small external field is applied thereto.

Magnetoresistance effects film

Disclosed are magnetoresistance effect films which have a magnetic thin film and an anti-ferromagnetically coupled magnetic multilayer thin film inserted into the interface between the non-magnetic thin film and the magnetic thin film, and a method for forming magnetoresistance effect films including the step of thermally treating the anti-ferromagnetic thin film and the magnetic multilayer thin film at a temperature of 200 to 300.degree. C. so as to generate one-directional anisotropy in the magnetic multilayer thin film, or the step of rotating by 90.degree. a magnetic field applied during the film formation so that the weak magnetization axes of the magnetic thin film and the magnetic multilayer thin film are orthogonal to each other.

Magnetoresistance effect film and method for making the same

A magnetoresistance effect film is disclosed. This magnetoresistance effect film comprises a substrate, at least two ferromagnetic thin films stacked one over the other on the substrate with a non-magnetic thin film interposed therebetween, and an antiferromagnetic thin film arranged adjacent to one of the ferromagnetic thin films. The antiferromagnetic thin film is a superlattice formed of at least two oxide antiferromagnetic materials selected from NiO, Ni.sub.x Co.sub.1-x O (0.1.ltoreq.x.ltoreq.0.9) and C.sub.o O. A biasing magnetic field Hr applied to the one ferromagnetic thin film located adjacent the antiferromagnetic thin film is greater than coercive magnetic force Hc.sub.2 of the other ferromagnetic thin film.

Magnetoresistance effect film and production process thereof

Magnetic thin films 2 and 3 are stacked on a substrate 4 with a nonmagnetic thin film 1 interposed therebetween. An antiferromagnetic thin film 5 is arranged adjacent to one magnetic thin film 3. The inequality Hc.sub.2 &lt;Hr is satisfied between a bias magnetic field Hr of the antiferromagnetic thin film 5 and coercive force Hc.sub.2 of the other magnetic thin film 2. At least a part of the antiferromagnetic thin film 5 comprises NiMn of an fct structure. Alternatively, the antiferromagnetic thin film 5 comprises a two-layer structure composed of a CoO layer deposited on a NiO layer to a thickness between 10 and 40 angstroms.

Magnetoresistance effect film, a method of manufacturing the same, and

A magnetoresistive element includes a first magnetic layer; and laminations of a second magnetic layer, a non-magnetic layer and a third magnetic layer. The laminations are adjacent to the first magnetic layer. The second magnetic layer and the third magnetic layer have different coercive forces, wherein the first magnetic layer is selected from CoCrTa, NdFe, and alloys thereof.

Magnetoresistive element

The invention provides a magnetoresistance effects film including (a) at least two thin magnetic films deposited on a substrate, (b) at least one thin nonmagnetic film interposed between the thin magnetic films, and (c) a thin antiferromagnetic film disposed adjacent to one of the thin magnetic films between which the thin nonmagnetic film is interposed. A bias magnetic field of one of the thin magnetic films induced by the thin antiferromagnetic film has an intensity Hr greater than a coercivity H.sub.C2 of the other of the thin magnetic films which is remote from the thin antiferromagnetic film (Hr&gt;H.sub.C2). The thin antiferromagnetic film has a superlattice structure composed of at least two of NiO, Ni.sub.x Co.sub.1-x O (x=0.1-0.9) and CoO. A ratio of Ni relative to Co in the number of atoms in the superlattice structure is set equal to or greater than 1.0. The magnetoresistance effects film exhibits large linear change in resistance with the hysteresis being small even when a small external field is applied thereto.

The magnetoresistive effect element in accordance with the invention has several aspects. For instance, the magnetoresistive effect element includes an artificial lattice multilayered structure composed of a thin magnetic layer and a non-magnetic layer at least once successively deposited, and a bias field applying device for applying a bias magnetic field to the artificial lattice multilayered structure so that an orientation of residual magnetization of one of the thin magnetic layers having a greater coercive force than that of an adjacent thin magnetic layer, is the same as an orientation of a bias magnetic field to be applied to the artificial lattice multilayered structure. The magnetoresistive effect element provides enhanced regenerated outputs and also improves the symmetry of regenerated waveforms.

Magnetoresistive effect element

A magnetoresistance effect film is disclosed. This magnetoresistance effect film comprises a substrate, at least two ferromagnetic thin films stacked one over the other on the substrate with a non-magnetic thin film interposed therebetween, and an antiferromagnetic thin film arranged adjacent to one of the ferromagnetic thin films. The antiferromagnetic thin film is a superlattice formed of at least two oxide antiferromagnetic materials selected from NiO, Ni.sub.x Co.sub.1-x O (0.1.ltoreq.x.ltoreq.0.9) and C.sub.o O. A biasing magnetic field Hr applied to the one ferromagnetic thin film located adjacent the antiferromagnetic thin film is greater than coercive magnetic force Hc2 of the other ferromagnetic thin film.

Growing community of inventors

Tokyo, Japan

Jun-Ichi Fujikata