Alps Electric Co., Ltd.

Alps Green Devices Co., Ltd.

Naruaki Oki

Sumihito Morita

Toshinori Watanabe

Hisayuki Yazawa

Hiroko Shinozaki

Kiyoshi Kobayashi

Kiyoshi Sato

Yoshihiro Nishiyama

Minoru Yamada

Hideki Gochou

Yoshihiro Kanada

Katsuya Kikuiri

Akira Koyama

Hiromi Ikegami, Legal Representative

Chiaki Ikegami, Legal Representative

Takashi Arai

An electrical current sensor includes a first laminated body having a magnetic detection element disposed over a first substrate, a protective film formed over the first substrate and the magnetic detection element, and a coil formed over the protective film, and a second laminated body having a shield layer formed over a second substrate and which is formed by bonding the first laminated body and the second laminated body to each other with an adhesion layer interposed therebetween such that the magnetic detection element and the shield layer face each other.

Electrical current sensor and method of manufacturing the same

In a thin-film magnetic head, a lower magnetic pole layer and a planarizing magnetic layer in continuity with the lower magnetic layer are arranged. Since a coil formation surface is positioned lower than the top surface of the lower magnetic pole layer and the planarizing magnetic layer, the front end of an upper magnetic core layer is formed to be a predetermined track width with a high accuracy. A thin-film magnetic head having good information writing characteristics and a method for manufacturing the thin-film magnetic head are thus provided.

Thin-film magnetic head having lower magnetic pole layer and insulator layer behind the lower magnetic pole layer in the direction of height of the pole layer, and method for manufacturing the thin-film magnetic head

A magnetic head in which two sides, which are defined as viewed in a core width direction, of first, second, and third end surfaces of a magnetic recording head extend along a longitudinal direction of recording tracks, so that it is possible to reduce spreading of leakage magnetic field extending from the two sides of the magnetic recording head in the core width direction between an upper core layer and a lower core layer protrusion through a gap layer. If the leakage magnetic field extending from both sides of the gap layer is reduced, it is possible to prevent the formation of an erased area beyond a multiple recording area. It is possible to maintain the S/N ratio of a reproduction signal at a proper value when reading out magnetic information from a magnetic tape.

Magnetic head, magnetic tape device including the magnetic head and method for producing the magnetic head

A gap depth determining insulating layer is formed on a lower core layer. A curved face is formed on a front edge face of the gap depth determining insulating layer so as to gradually depart from an ABS surface from the bottom at the lower core layer to the top of the curved face. A back end of an upper magnetic layer can be formed on the gap depth determining insulating layer, whereby the volume of the upper magnetic layer can be increased while a gap depth is maintained at a predetermined length.

Thin-film magnetic head having a high recording density and frequency

A thin film magnetic head wherein a partial insulating layer is formed on a bottom pole layer with a gap layer provided therebetween, the gap depth Gd being regulated by the distance from a surface facing a recording medium to the partial insulating layer. A magnetic flux partially leaks from a tip region of an upper core layer to the bottom pole layer through the partial insulating layer to effectively suppress magnetic saturation of the tip region, thereby improving the NLTS characteristic and PW50 characteristic, and suppressing the occurrence of side fringing.

Method of manufacturing thin film magnetic head having partial insulating layer formed on bottom pole layer through gap layer

Thin film magnetic head having partial insulating layer formed on bottom pole layer through gap layer and method of manufacturing the same

A thin film magnetic head wherein a partial insulating layer is formed on a bottom pole layer with a gap layer provided therebetween, the gap depth Gd being regulated by the distance from a surface facing a recording medium to the partial insulating layer. A magnetic flux partially leaks from a tip region of an upper core layer to the bottom pole layer through the partial insulating layer to effectively suppress magnetic saturation of the tip region, thereby improving the NLTS characteristic and PWcharacteristic, and suppressing the occurrence of side fringing.

By forming a step in a lower core layer, the distance between the upper surface of a Gd-defining layer and the lower core layer is changed stepwise. Consequently, the distance between an upper magnetic pole layer formed on the upper surface of the Gd-defining layer and the lower core layer is small in the front region of the lower core layer, and thus a leakage magnetic field from the upper magnetic pole layer is absorbed by the lower core layer and is not applied to a recording medium.

Thin-film magnetic head capable of suppressing side fringing

A metal film is formed on the upper surface of a gap-depth defining layer. This makes it possible to form an upper magnetic layer with a predetermined thickness over a gap layer and the metal film by plating, and to produce a thin-film magnetic head which can reduce the magnetic saturation. The positions of a rear edge of the upper magnetic layer or the like, which contributes to the characteristics, such as overwriting characteristics, can be easily and freely changed in order to optimize the characteristics, and the controllability of the track width can be enhanced.

Thin-film magnetic head having metal film formed on gap-depth defining layer, and production method therefor

In a thin-film magnetic head, an lower magnetic pole layer is formed on a lower core layer to form a step between the lower core layer and the lower magnetic pole layer. A coil layer and a coil-insulating layer are formed on the lower core layer, and an upper core layer is formed over the lower magnetic pole layer and the coil-insulating layer. This configuration decreases the height of the coil-insulating layer from the lower magnetic pole layer compared to the height in a conventional thin-film magnetic head. The front end of the upper core layer can be precisely formed so as to have a track width Tw. This thin-film magnetic head is suitable for narrower track widths.

Thin-film magnetic head suitable for narrow tracks

A lower magnetic pole layer is formed on a lower core layer, and a coil layer and a coil insulating layer are formed in a space corresponding to a level difference between the lower magnetic pole layer and the lower core layer. The coil layer and the coil insulating layer are leveled flush with a reference plane, whereby a gap layer can be formed flat on the lower magnetic pole layer, the coil layer and the coil insulating layer. Thus, since the upper core layer can be directly formed on the gap layer and the gap layer can be formed on the flat surfaces, it is possible to form the upper core layer into a predetermined shape with high accuracy and to manufacture a thin-film magnetic head which is adaptable for a decrease of the track width in future.

Thin-film magnetic head capable of narrowing track width and method of manufacturing the same

To provide a thin film magnetic head having an upper core layer whose dimensions are controlled with high precision, which can yield high density recording on a magnetic recording medium, and a production process of the same, an upper core layer is formed on a first, second and third insulation layers and a gap layer, and has a narrow tip region, a connecting portion and a body portion, in which the tip region is connected via the gap layer to a lower core layer on a head surface facing a magnetic recording medium, the connecting portion is connected to the tip region in a nearly identical width, and is formed on a lower region of a first sloping region and an inclined plane K, and the body portion extends wider from the connecting portion and covers part of a coil layer. In a thin film magnetic head having a dual coil layer structure, a third insulation layer having a third apex and a third sloping region is formed to cover a second coil layer, and the third apex is located on a second plane region, and the top of a second insulation layer and the third sloping region establish a first pocket region P

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Niigata-ken, Japan

Naruaki Oki