Alps Electric Co., Ltd.

Tdk Corporation

Yasuo Hayakawa

Yoshihiro Nishiyama

Naoya Hasegawa

Akihiro Makino

Masamichi Saito

Yosuke Ide

Eiji Umetsu

Takashi Hatanai

Kenji Honda

Daigo Aoki

Yutaka Naito

Naohiro Ishibashi

Kiyohito Yamasawa

Akihisa Inoue

Tsuyoshi Masumoto

Toshihiro Kobayashi

Satoshi Waga

Hideki Kamimura

Motoki Hirayama

Masaya Yamatani

Teruo Bitoh

Digo Aoki

Kumiko Ominato

Masahlko Ishizone

Photo detector

At both sides of an element portion, a first hard bias layer having a higher residual magnetization Mr and a second hard bias layer having a higher coercive force Hc are deposited in that order from the bottom with one end of the first hard bias layer being closed close to a free magnetic layer. A film thickness ratio of the first hard bias layer in a whole hard bias layer is from 35% to 75%. This stabilizes magnetization in the free magnetic layer to reduce asymmetry, thus enabling improvement in stability of reproducing characteristics including noise suppression.

Tunneling magnetic sensing element having two-layered hard bias layer

A CPP giant magnetoresistive head includes lower and upper shield layers, and a giant magnetoresistive element disposed between the upper and lower shield layers and including a pinned magnetic layer, a free magnetic layer and a nonmagnetic layer disposed between the pinned magnetic layer and the free magnetic layer. In the CPP giant magnetoresistive head, the pinned magnetic layer extends to the rear of the nonmagnetic layer and the free magnetic layer in the height direction, and the dimension of the pinned magnetic layer in the height direction is larger than that in the track width direction. Also, the pinned magnetic layer comprises a magnetic material having a positive magnetostriction constant or a magnetic material having high coercive force, and the end of the pinned magnetic layer is exposed at a surface facing a recording medium.

CPP GMR head with antiferromagnetic layer disposed at rear of ferrimagnetic pinned layer

A lower shield layer has a substantially flat shape, and an upper shield layer has a front portion and a rear portion, where the front portion is disposed closer to the lower shield layer than the rear portion. A lower conductive electrode and an upper conductive electrode are disposed between the lower shield layer and the upper shield layer. The lower conductive electrode is electrically connected to the lower shield layer, and the upper conductive electrode is electrically connected to the upper shield layer. Since the lower and upper conductive electrodes are disposed between the upper and lower shield layers, each of the lower shield layer and the upper shield layer may be formed to have a small area and a simple shape.

Magnetic head device provided with lead electrode electrically connected to magnetic shield layer

A magnetic sensing element including a laminate and a bias layer is provided. A first reactive-ion-etching (RIE) stop layer is disposed on a free magnetic layer. Second RIE stop layers are disposed on bias layers. The first and second RIE stop layers function as stop layers when layers on the first and second RIE stop layers are removed by reactive ion etching in a production process. Reactive ion etching is completed when the first RIE stop layer and the second RIE stop layers are exposed, the first and second RIE stop layers being disposed at almost the same height. Also provided is a process for producing the magnetic sensing element.

Magnetic sensing element having reactive-ion-etching stop layer and process for producing same

Self-pinned CPP giant magnetoresistive head with antiferromagnetic film absent from current path

A CPP giant magnetoresistive head includes a lower shield layer; an upper shield layer; and a giant magnetoresistive element (GMR) between the lower shield layer and the upper shield layer. The GMR includes a nonmagnetic material layer; a pinned magnetic layer; and a free magnetic layer. The pinned layer and the free layer are laminated with the nonmagnetic layer provided therebetween. A current flows perpendicularly to a film plane of the GMR, the pinned magnetic layer extends in the height direction longer than in a track-width direction and includes a first portion in the GMR. The first portion is disposed above or below the nonmagnetic layer and the free layer. A second portion is behind the nonmagnetic layer and the free layer in the height direction. The first and second portions are in the same plane. The width of the pinned layer in the track-width direction in the first portion is greater than that in the second portion.

CPP giant magnetoresistive head including pinned magnetic layer that extends in the height direction

A CPP giant magnetoresistive head includes lower and upper shield layers with a predetermined distance therebetween, and a giant magnetoresistive element (GMR) including pinned and free magnetic layers disposed between the upper and lower shield layers with a nonmagnetic layer interposed between the pinned and free magnetic layers. A current flows perpendicularly to the film plane of the GMR. The magnetoresistive head further includes an antiferromagnetic layer (an insulating AF of Ni&#x2014;O or &#x3b1;-FeO) provided in the rear of the GMR in a height direction to make contact with the upper or lower surface of a rear portion of the pinned magnetic layer which extends in the height direction, and an exchange coupling magnetic field is produced at the interface with the upper or lower surface, so that the magnetization direction of the pinned magnetic layer is pinned by the exchange coupling magnetic field in the height direction.

CPP giant magnetoresistive head having antiferromagnetic film disposed in rear of element

A thin film magnetic head includes a gap layer which may be made of a SiON film to increase Young's modulus E to about 123.3 (GPa) or more. As a result, the gap layer is less pushed from a surface facing a recording medium in the height direction during lapping of the surface facing the recording medium, thereby decreasing the amount of protrusion of the gap layer from the facing surface as compared with a conventional magnetic head.

Thin film magnetic head comprising SiON film

A current limiting layer including a mixture of a conductive portion and an insulating portion is provided on the side (upper side) of a free magnetic layer which a sensing current reaches. This can decrease the effective element area while maintaining the large optical element area. Therefore, a magnetic sensing element can easily be formed by using a photolithography technique having the same degree of accuracy as a conventional technique, and a CPP type magnetic sensing element having high reproduced output can be manufactured.

Magnetic sensing element permitting decrease in effective element size while maintaining large optical element size

A thin film magnetic head includes a lower gap layer and/or an upper gap layer made of an AlSiO film having a Si content of 2 at % to 9 at % of the total or an AlSiON film further having a N content of 2 at % to 10 at %. Therefore, the insulation performance, developer resistance, smoothness and heat radiation property of the gap layer can be improved as compared with a gap layer made of Al O .

Thin film magnetic head using Al-Si-O insulating material and method of manufacturing the same

An insulation barrier layer is formed using an insulating material expressed by a composition formula of Al&mdash;Si&mdash;O or Si&mdash;O&mdash;N. The insulation barrier layer is therefore able to have improved dielectric strength, developer resistance, smoothness, and heat radiation.

Magnetic sensor capable of providing stable resistance change rate

The present invention provides a thin film magnetic head that can efficiently dissipate the heat generated by the stationary sensing current, suppress heat diffusion, firing loss, decrease of output levels and deterioration of exchange anisotropic magnetic field as well as being excellent in linear responses and having suppressed Barkhausen noises, wherein the magnetic head comprises at least the magnetoresistive element layer deposited on the lower shield layer via lower gap layer, and the upper shield layer deposited on the electrode layer via the upper gap layer, at least one of the lower gap layer and upper gap layer comprising the highly heat-conductive insulation layer containing at least Al, N, X and O, wherein X is one or plural kinds of the element selected from Si, B, Ge and C.

Thin film magnetic head

A thin magnetic element comprising a coil pattern formed on at least one side of a substrate and a thin magnetic film formed on the coil pattern, wherein, assuming that the thickness and width of a coil conductor constituting the coil pattern are t and a, respectively, an aspect ratio t/a of the coil conductor satisfies the relationship 0.035&lE;t/a&lE;0.35, and the thin magnetic film has a resistivity of 400 &mgr;&OHgr;cm or more.

Thin magnetic element and transformer

In the formation of an AlN film as a gap layer of a thin film magnetic head, the mean crystal grain size of the AlN film can be regulated in the range from 85 angstroms to 130 angstroms to improve the denseness of the film, by connecting a radio frequency power source also to a substrate-supporting unit and supplying bias power of 17 W to 40 W to the substrate-supporting unit. The AlN film can have, therefore, improved head dissipation, corrosion resistance against an alkali solution, higher hardness, higher surface resistance and lower surface roughness. There is also disclosed a thin film magnetic head comprising at least a magnetoresistive element layer formed on a lower shield layer with the interposition of a lower gap layer, a lead layer for imparting a sensing current to the magnetoresistive element layer, and an upper shield layer formed on the lead layer with the interposition of an upper gap layer, in which at least either of the lower and upper gap layers has an Al&mdash;N&mdash;X system insulating layer, the element X being at least one element selected from Si, B, Cr, Ti, Ta and Nb.

Growing community of inventors

Niigata-ken, Japan

Yasuo Hayakawa