Hitachi, Ltd.

Hitachi Global Storage Technologies Japan, Ltd.

Hitachi Global Storage Technologies

Chiaki Ishikawa

Hideo Todokoro

Toshio Kobayashi

Hisashi Takano

Tohru Ishitani

Hideo Tanabe

Kazuo Shiiki

Naoki Koyama

Isamu Yuito

Tsuyoshi Ohnishi

Eijin Moriwaki

Hiroyuki Hoshiya

Kazuhiro Nakamoto

Kaori Totsuka

Atsushi Nakamura

Katsuro Watanabe

Hiromasa Takahashi

Hisashi Kimura

Takashi Kawabe

Norifumi Miyamoto

Akira Morinaga

In a narrow magnetoresistive head having a magnetic domain control film comprising a single layer of magnetic film or magnetic films antiferromagnetically coupled by means of a nonmagnetic member, it has been found that the magnetic domain can be controlled with a smaller magnetization film thickness product than anticipated so far and the range is defined relative to the geometrical track width in the present invention. By defining the magnetization film thickness product of the magnetic domain control film within a prescribed range of the invention, a magnetic head having higher output than usual and having stable output with no hysteresis in the transfer curve and with no output fluctuation can be attained.

Magnetoresistive head having defined relationships between the tract width and magnetization film thickness product to permit no hysteresis in the transfer curve

A magnetic recording head includes an upper shield layer, a lower shield layer, a magnetoresistive film interposed between the upper shield layer and the lower shield layer, and a pair of leads electrically coupled to the magnetoresistive film, in which a pair of side shield layers constituted by portions of the upper shield layer is formed on both sides of the magnetoresistive film, and a spacing between each side shield layer and the magnetoresistive film is formed to be narrower than twice of a spacing between the upper shield layer and the lower shield layer, thereby a side reading amount can be made smaller than a conventional side reading value determined from the spacing between the upper and lower shield layers and a magnetic spacing between the head and a medium.

Magnetic recording and reproducing head restraining a side reading

In a giant magnetoresistive head, a magnetic read width is reduced and a read output is increased. The giant magnetoresistive head has a magnetoresistive film having a pinned layer, a non-magnetic layer, and a free layer, a pair of terminals for applying a current to the magnetoresistive film, and bias applying means for applying a bias magnetic field for magnetic domain control to the free layer. The free layer has a sensing region and a pair of out-of-sensing-region regions on both ends of the sensing region. The magnetization direction of one of the out-of-sensing-region regions and the magnetization direction of the other out-of-sensing-region region have different components in a direction of element height of head. The magnetization of the one out-of-sensing-region region and the magnetization of the other out-of-sensing-region region are nearly symmetrical relative to the sensing region interposed therebetween.

Magnetoresistive head

Magnetic recording head

In a composite magnetic head comprising a magnetoresistive read head including a magnetic thin film having a magnetoresistive effect and soft magnetic members interposing the soft magnetic film between them through a non-magnetic insulation layer, an induction type write head including poles formed in a moving direction of a medium and a conductor crossing the poles, and disposed in the proximity of the magnetoresistive head, and a substrate supporting these heads, the present invention discloses a composite magnetic head characterized in that part of a floating surface inclusive of the magnetic head constituent members has recesses and the read/write operations to and from the medium are effected by the portion interposed by these recesses.

Combination perpendicular magnetic head having shield material formed at both ends of an upper pole of a write element

A magnetoresistive head has a magnetoresistive element including an antiferromagnetic layer, a second magnetic layer on the antiferromagnetic layer, a non-magnetic interlayer on the second magnetic layer, and a first magnetic layer on the non-magnetic interlayer. The first magnetic layer has at least one region at an end thereof which has a smaller saturation magnetization than the central part of the first magnetic layer. The end region has a width Xe (in the track width direction) defined by 0.08&lE;Xe/Twr&lE;0.2, where Twr denotes the track width. The magnetoresistive element is held between an upper shield and a lower shield. The effect of this construction is that the end regions of the first magnetic layer are more affected by the longitudinal bias field than the central part of the first magnetic layer. Consequently, the occurrence of magnetic domains is efficiently suppressed in the end regions of the first magnetic layer.

Magnetoresistive sensor, thin-film read/write head, and magnetic recording apparatus using the sensor

Magnetic head having track width defined by trench portions filled with magnetic shield material

A magnetic head include a pair of magnetic shield layers, a pair of gap layers formed between the pair of magnetic shield layers, a magnetoresistive layer arranged between the pair of gap layers, and a pair of electrodes electrically connected to the magnetoresistive layer. At least one of the pair of magnetic shield layers is formed as a discontinuous multi-layer or as a mixed layer.

Magnetic head having magnetic shield layers

In a composite magnetic head comprising a magnetoresistive read head including a magnetic thin film having a magnetoresistive effect and soft magnetic members interposing the soft magnetic film between them through a non-magnetic insulation layer, an induction type write head-including poles formed in a moving direction of a medium and a conductor crossing the poles, and disposed in the proximity of the magnetoresistive head, and a substrate supporting these heads, the present invention discloses a composite magnetic head characterized in that part of a floating surface inclusive of the magnetic head constituent members has recesses and the read/write operations to and from the medium are effected by the portion interposed by these recesses.

Method of fabricating a magnetic head by focused ion beam etching

The present invention is to realize a magnetic recording and reproducing apparatus in which even if a spacing between shields of a magnetic head is narrowed, a deterioration in characteristic caused by a short-circuiting between a magnetoresistive layer and a magnetic shield layer is prevented to provide a high recording density. The present invention comprises an upper shield layer a lower shield layer and a magnetoresistive layer arranged therebetween. Further, there is provided a constitution in which one or both shield layers has (have) a high resistance layer comprising a mixed layer of ferromagnetic metal and an insulating material, or a discontinuous multi-layer having a plurality of ferromagnetic metal layers and a plurality of insulating material layers laminated alternately, to prevent a deterioration in characteristic caused by a short-circuiting.

Magnetic head with shield layer having discontinuous multi-layer or mixed layer and magnetic recording apparatus utilizing the magnetic head

A giant magnetoresistive sensor which is improved in reproduction output and peak asymmetry of read-back waveform. It is composed of a first free ferromagnetic film, a first non-magnetic film, a composite ferromagnetic film, a second non-magnetic film, and a second free ferromagnetic film, which are laminated sequentially, but has no antiferromagnetic film to fix said composite ferromagnetic film, and said composite ferromagnetic film contains a first, second, and third ferromagnetic film, which are antiferromagnetically coupled with one another, and also contains films which separate said ferromagnetic films from one another and antiferromagnetically couple them with one another.

Giant magnetoresistive sensor, thin-film read/write head and magnetic recording apparatus using the sensor

Narrow track thin film head including magnetic poles machined by focused ion beam etching

Narrow track thin film head having a focused ion beam etched air bearing surface

Narrow track thin film magnetic head suitable for high density recording

Growing community of inventors

Kokubunji, Japan

Chiaki Ishikawa