Hitachi, Ltd.

Tooru Takeura

Masahiro Kitada

Kazuhiro Momata

Yoshihisa Kamo

Noboru Shimizu

Hideo Tanabe

Hitoshi Nakamura

Isamu Yuito

Makoto Morijiri

Tetsuo Kobayashi

Naoki Sato

Yukihisa Tsukada

Kazuyoshi Adachi

Masao Katsumata

Hiroshi Yamamoto

Naoki Koyama

Yoshiki Hagiwara

Masahide Suenaga

Kousaku Chida

Toshikane Yoshimatsu

Katsunori Ohwada

Shigeyoshi Kato

Takahiro Katoh

Masayoshi Waki

A novel magtnetoresistive head unit includes an upper shield film and a lower shield film electrically connected to electrodes connected with an external source which are shorted by a shorting circuit without the intermediary of an MR element. The current due to static electricity generated in the process of element formation is made to flow through the shorting circuit thereby to prevent the electrostatic breakdown of the MR element and the dielectric breakdown between the MR element and the shield films. After cutting out a slider from the substrate, the upper and lower shield films are shorted by the shorting circuit, thereby preventing the electrostatic breakdown of the magnetoresistive element and the dielectric breakdown between the magnetoresistive element and the shield films during the assembly and transportation. The electrostatic breakdown is also prevented in the processes from the formation of the magnetoresistive (MR) element to the mounting of the MR element on the apparatus, thereby making it possible to fabricate an MR head and a write-read separated magnetic head with a high yield.

Method of fabricating magnetoresistive effect type magnetic head capable

A magnetoresistive head is fabricated with a high yield rate by preventing the electrode film from breaking down. An upper shield film is formed with an electrode separation layer and an upper gap film disposed between it and the electrode film. The electrode film is prevented from being etched when the upper shield film is subjected to ion milling as a result. Further, the upper gap film is laid on top of the electrode separation layer, and a lead is satisfactorily protected and prevented from being exposed. Thus, the upper shield film and the lead are prevented from becoming short-circuited as a result of the disconnection of the electrode film and the exposure of the lead.

Magnetoresistive head structure that prevents under film from

A magnetoresistive head is disclosed. It comprises a lower gap film, a magnetoresistive film, a bias film, an electrode, an upper gap film, and upper shield film provided in sequence on a substrate. A protective film is provided under the upper shield film to prevent the upper gap film and electrode from the undesirable etching during patterning the upper shield film.

Magnetoresistive head

A magnetic recording/reproducing head assembly comprising a first magnetic path forming member on which a coil is mounted, a second magnetic path forming member which forms a magnetic path in cooperation with the first magnetic path forming member, and a film laminate formed at a front gap portion between the first magnetic path forming member and the second magnetic path forming member. The film laminate includes a magnetic detecting element for detecting a change in a magnetic field and a soft magnetic film or films. This magnetic head assembly is prepared by forming the film laminate on a head base of the head assembly, bonding a core member to the head base with the film laminate formed thereon, and mounting a coil on the core member.

Magnetic recording/reproducing head assembly

A thin-film magnetic head has a first ferrite block on which a plurality of transducing elements are aligned on a predetermined surface, and a second ferrite block bonded to the first ferrite block, and has multi-track capabilities in accordance with the transducing elements. Eithr bonding surface of the first and second ferrite block is formed with an insulating film layer, the entire bonding surface is coated with an adhesive or formed with a plurality of recesses to be externally filled with the adhesive, and the adhesive is filled in gaps defined by the recesses and the surface of the opposed ferrite block. Thus, since the bonding portions of the first and second ferrite blocks are distributed over a wide region, the bonding strength can be largely increased, the transducing gap lengths are uniformly maintained, and the transducing element characteristic is not affected by the aging of the adhesive thereby improving the reliability of the magnetic head.

Thin-film magnetic head with a plurality of transducers

The magnetic head according to the present invention has a ferrite substrate and closure. The ferrite substrate has formed therein a first recess in which a conductive coil is to be deposited, while the ferrite closure has formed therein a second recess enclosing a portion of the conductive coil that is contributed to at least signal transducing. The end of the second recess is disposed in a position related with the depth of the tranducing gap. Since the first recess in which the conductive coil is deposited has no influence on the magnetic transducing efficiency, it can be much freely formed by photolithography or reactive ion etching. Also since the second recess having an influence on the magnetic transducing efficiency can be formed by precision machining, no advanced process control is needed.

Magnetic head closure having ferrite substrate and closure and

The use of a pure zirconium film as a shunt film in a magnetoresistive head having a permalloy film as a magnetoresistive film and a shunt film for application of a transverse biasing magnetic field serves to improve the heat resistance of the magnetoresistive element and allows an increase in the temperature used in the process for producing a magnetic head.

Magnetoresistive magnetic head including zirconium sheet film

A soft-film-bias type magnetoresistive device is disclosed in which a high-permeability magnetic film, an insulating film and a permalloy film are formed on a substrate in this order, and first, second and third electrodes, which are parallel to each other, are provided on the permalloy film, to form a differential type magnetoresistive device. In this magnetoresistive device, a bias magnetic field which is generated and applied to the permalloy film between the first and second electrodes, is opposite in direction to a bias magnetic field which is generated and applied to the permalloy film between the second and third electrodes.

Soft-film-bias type magnetoresitive device

A magnetoresistance type magnetic head, in which a magnetoresistance film is disposed through an insulating film between two soft magnetic bodies, and a signal leadout conductor for the magnetoresistance film is disposed in the insulating film so that its surface is at the same level as that of the insulating film, thereby providing a high-performance magnetoresistance type magnetic head, in which the gap length is small and the resistance of the signal leadout conductor portion is small.

Magnetoresistance type magnetic head and method for fabricating same

The present invention relates to the structure of a magneto-resistive head for reducing the spike noises generated in the head and for increasing the signal to noise ratio when the information is reproduced. In order to achieve the object, an electric conductor layer is disposed at both sides or one side of a magneto-resistive element, and the conductor layer is isolated from the element and connected to a DC potential.

Magneto-resistive head for protecting against output spike noises

In a magnetoresistive sensor having a magnetoresistive effect element which is held between two sheets of high permeability magnetic ferrite with insulating layers interposed between them, a ferromagnetic metal film is provided adherently to the high permeability magnetic ferrite between the ferrite and the insulating layer, a rise in temperature of the magnetoresistive effect element thereby being held down and a reproduced waveform being made sharp, and thus the characteristics of the element being improved with the life thereof prolonged.

Magnetoresistive sensor having magnetic shields of ferrite

Disclosed is a magnetic transducer using a magnetoresistance effect, comprising a magnetoresistive film, a hard magnetic film for applying a transverse biasing magnetic field thereto, and a conductive film through which current for applying the transverse biasing magnetic field to the magnetoresistive film flows. The conductive film may be either in electrical contact with or in electrical insulation from the magnetoresistive film. In this magnetic transducer, even when the heights of the respective constituents have changed, the transverse biasing magnetic field to be applied does not change considerably, and an optimum bias field strength is readily attained.

Magnetic transducer using magnetoresistance effect

A method of forming a multilayer thin film is disclosed in which a second thin conductive film is deposited on a first thin conductive film uninterruptedly after the first thin film has been deposited on a substrate, the first and second films thus formed are processed so as to form a predetermined pattern, the surface of the second thin film is cleaned by ion etching and a third thin conductive film is deposited on the whole surface of the substrate, and then the second and third thin films are processed so as to have a pattern different from the above-mentioned predetermined pattern. In the case where two thin conductive films different in material and pattern from each other are piled on a substrate, the above method can form a perfect interconnection between the two films and can make very small the contact resistance between the two films. Accordingly, the method is fit to form, for example, a barber pole type magnetoresistive element.

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Odawara, Japan

Tooru Takeura