Hitachi Global Storage Technologies Netherlands B.v.

Hitachi, Ltd.

Hitachi Global Storage Technologies Japan, Ltd.

Masahiko Hatatani

Kenichi Meguro

Katsuro Watanabe

Chiseki Haginoya

Hiroyuki Hoshiya

Kazuhiro Nakamoto

Katsumi Hoshino

Hisashi Kimura

Hiroshi Ide

Kouichi Nishioka

Kikuo Kusukawa

Taku Shintani

Nubuo Yoshida

Chiaki Ishakawa

Embodiments of the present invention provide a magnetic head having a read head of stable reading operation and with less magnetic fluctuation noise. According to one embodiment, a free layer has a structure comprising two ferromagnetic layers (a first free layer and a second free layer) that are coupled anti-ferromagnetically by way of a non-magnetic intermediate layer, in which the magnetization amount of the first free layer is set to larger than the magnetization amount of the second free layer. Further, the magnetic domains in the first free layer and the second free layer are stabilized simultaneously by increasing the distance between the second free layer and the magnetic domain control film to be more than the distance between the first free layer and the magnetic domain control film, thereby adjusting the magnetization amount of the magnetic domain control film. Further, the volume of the entire free layer is increased thereby greatly decreasing the magnetic fluctuation noises, to obtain a read head showing a high SN ratio.

Magnetic head and manufacturing method thereof

Embodiments of the invention provide a magnetic recording and read head which reduces the spread read width in a narrow track having a width of 100 nm or less and shows stable read operation. In one embodiment, a side magnetic shield has a multi-layered structure including non-magnetic separate layers and soft magnetic layers, and the soft magnetic layers are magnetized in opposite directions to reduce a magnetic field induced by the side magnetic shield.

Magnetic head with laminated side shields

A magnetoresistive head and a fabricating method thereof accomplishing high sensitivity and low noise are provided even if track width narrowing makes progress. In one embodiment, a pinned layer includes a laminate which includes at least two magnetic layers and where adjacent magnetic layers are coupled antiferromagnetically to each other, and a mechanism to apply a longitudinal biasing field to a free layer is made to function by laminating a nonmagnetic separate layer/longitudinal biasing layer/antiferromagnetic layer connecting the free layer and opposite a nonmagnetic conductive layer (or nonmagnetic tunneling barrier layer). Controlling a magnetization direction of the longitudinal biasing layer which bears application of a longitudinal biasing field to the pinned layer and free layer is achieved by annealing carried out while applying a magnetic field in a track width direction and applying a magnetic field at room temperature.

Magnetoresistive head with improved in-stack longitudinal biasing layers

In a side shield structure employed to narrow the effective track, a noise caused by the side shield structure can be reduced. In one embodiment, the side shield is inclined with respect to the film plane to suppress the generation of a magnetic pole in the end portion of the side shield. To this end, the side face of a device is inclined at a desired angle. Further, a reproduction device is formed at two or more angles &#x3b2;and &#x3b2;to improve the track width accuracy.

Magnetic head with side shield and manufacturing method thereof

Embodiments of the invention provide a spin-valve type magnetic head that satisfies the requirements of both high read output and stability with narrow tracks. In one embodiment, a domain control film is formed on a magnetoresistive layered film in the same track width. A double closed flux path structure that uses three magnetic layers is employed with magnetic coupled structure in both ends of the track. The three magnetic layers are a soft magnetic free layer, a domain-stabilization ferromagnetic layer, and a soft magnetic anti-parallel layer.

Magnetic head with domain stabilization and magnetic recording/reproducing apparatus using the same

A magnetic sensor includes a spacer having at least a nonmagnetic metal layer inserted between the upper shield layer and the longitudinal bias layers or between the upper shield layer and the longitudinal bias layers plus the magnetoresistive film, the shortest distance between the longitudinal bias layers and the free layer of the magnetoresistive film is set smaller than the shortest distance between the longitudinal bias layers and the upper shield layer, and this arrangement ensures that the amount of magnetic flux entering the magnetoresistive film from the longitudinal bias layers is larger than that absorbed by the upper shield layer, thus realizing a magnetic sensor whose Barkhausen noise is suppressed.

Magnetic sensor having a free layer containing a single magnetic domain

To provide a spin-valve type magnetic head having high read output even if track width is narrow and high stability, a magnetic head according to the invention is provided with a spin-valve type magnetoresistive element in which a single magnetic domain turning ferromagnetic layer is formed on a soft magnetic free layer via a non-magnetic separating layer, the soft magnetic free layer and the single magnetic domain turning ferromagnetic layer are magnetostatically coupled at the end of track width, a closed magnetic circuit is formed and the soft magnetic layer has magnetization substantially induced in a direction substantially perpendicular to an external magnetic field.

Growing community of inventors

Kanagawa, Japan

Masahiko Hatatani