Kabushiki Kaisha Toshiba

Takeo Sakakubo

Masatoshi Yoshikawa

Masashi Sahashi

Hitoshi Iwasaki

Katsuhiko Koui

Tomohiko Nagata

Hiroaki Yoda

Masayuki Takagishi

Hiromi Yuasa

Michiko Hara

Yuzo Kamiguchi

Akio Hori

Susumu Hashimoto

Kohichi Tateyama

Yuichi Ohsawa

Naoyuki Inoue

Takashi Koizumi

Tadahiko Kobayashi

Jun Ito

Atsuhito Sawabe

Norio Ozawa

Kazushi Tanimoto

Hiromi Sakata

Takasi Koizumi

Kei Sakoda

Teruo Sasho

A magnetoresistance effect element includes a magnetoresistance effect film including a magnetically pinned layer having a magnetic material film whose direction of magnetization is pinned substantially in one direction, a magnetically free layer having a magnetic material film whose direction of magnetization changes in response to an external magnetic field, and a nonmagnetic metal intermediate layer located between said pinned layer and said free layer. The element also includes a pair of electrodes electrically connected to the magnetoresistance effect film to supply a sense current perpendicularly to a film plane of the magnetoresistance effect film. At least one of the pinned layer and the free layer may include a thin-film insertion layer. The nonmagnetic metal intermediate layer includes a resistance adjusting layer including at least one of oxides, nitrides and fluorides, and the thin-film insertion layer includes at least one element selected from the group consisting of iron (Fe), cobalt (Co) and nickel (Ni).

Magnetoresistance effect element having resistance adjusting layer and thin-film insertion layer

In a spin valve type element, an interface insertion layer () of a material exhibiting large spin-dependent interface scattering is inserted in a location of a magnetically pinned layer () or a magnetically free layer () closer to a nonmagnetic intermediate layer (). A nonmagnetic back layer () may be additionally inserted as an interface not in contact with the nonmagnetic intermediate layer to increase the output by making use of spin-dependent interface scattering along the interface between the pinned layer and the nonmagnetic back layer or between the free layer and the nonmagnetic back layer.

Magnetoresistance effect element, magnetic head and magnetic reproducing apparatus

A magnetoresistance effect element comprises a magnetoresistance effect film including a magnetically pinned layer whose direction of magnetization is pinned substantially in one direction, a magnetically free layer whose direction of magnetization changes in response to an external magnetic field, and a nonmagnetic intermediate layer located between the pinned layer and the free layer; and a pair of electrodes electrically connected to said magnetoresistance effect film to supply a sense current perpendicularly to a film plane of said magnetoresistance effect film, The intermediate layer has a first layer including a first region whose resistance is relatively high and second regions whose resistance is relatively low. The sense current preferentially flows through the second regions when the current passes the first layer. Alternatively, the concentration of oxygen in the first layer may have a two-dimensional fluctuation, and a first region where the concentration of oxygen is equal to or higher than 40 atomic % and a second region where the concentration of oxygen is equal to or lower than 35 atomic % may be provided in the first layer.

Magnetoresistance effect element, having a nonmagnetic intermediate layer having a two-dimensional fluctuation of resistance

A magnetoresistance effect element comprises a magnetoresistance effect film including a magnetically pinned layer whose direction of magnetization is pinned substantially in one direction, a magnetically free layer whose direction of magnetization changes in response to an external magnetic field, and a nonmagnetic intermediate layer located between the pinned layer and the free layer, and a pair of electrodes electrically connected to said magnetoresistance effect film to supply a sense current perpendicularly to a film plane of said magnetoresistance effect film. The intermediate layer has a first layer including a first region whose resistance is relatively high and second regions whose resistance is relatively low. The sense current preferentially flows through the second regions when the current passes the first layer. Alternatively, the concentration of oxygen in the first layer may have a two-dimensional fluctuation, and a first region where the concentration of oxygen is equal to or higher than 40 atomic % and a second region where the concentration of oxygen is equal to or lower than 35 atomic % may be provided in the first layer.

Magnetoresistance effect element having a nonmagnetic intermediate layer having a two-dimensional fluctuation of oxygen

A magnetoresistance effect element comprises a magnetoresistance effect film including a magnetically pinned layer whose direction of magnetization is pinned substantially in one direction, a magnetically free layer whose direction of magnetization changes in response to an external magnetic field, and a nonmagnetic intermediate layer located between the pinned layer and the free layer; and a pair of electrodes electrically connected to said magnetoresistance effect film to supply a sense current perpendicularly to a film plane of said magnetoresistance effect film. The intermediate layer has a first layer including a first region whose resistance is relatively high and second regions whose resistance is relatively low. The sense current preferentially flows through the second regions when the current passes the first layer. Alternatively, the concentration of oxygen in the first layer may have a two-dimensional fluctuation, and a first region where the concentration of oxygen is equal to or higher than 40 atomic % and a second region where the concentration of oxygen is equal to or lower than 35 atomic % may be provided in the first layer.

Magnetoresistance effect element having a nonmagnetic intermediate layer having a two-dimensional fluctuation of resistance

In a spin valve type element, an interface insertion layer ( ) of a material exhibiting large spin-dependent interface scattering is inserted in a location of a magnetically pinned layer ( ) or a magnetically free layer ( ) closer to a nonmagnetic intermediate layer ( ). A nonmagnetic back layer ( ) may be additionally inserted as an interface not in contact with the nonmagnetic intermediate layer to increase the output by making use of spin-dependent interface scattering along the interface between the pinned layer and the nonmagnetic back layer or between the free layer and the nonmagnetic back layer.

A method for manufacturing a magnetic head which includes a lower write pole having a projection, an upper write pole having a projection opposed to the projection of the lower write pole, and a magnetic gap interposed between the projection of the upper write pole and the projection of the lower write pole, comprising: a first step of making the magnetic gap on the projection of the lower write pole; a second step of making a non-magnetic material layer on the lower write pole, the non-magnetic material layer having a projection on its top surface in positional alignment with the projection of the lower write pole; a third step of making a mask layer on the non-magnetic material layer, the mask layer having an opening in which the top surface of the projection of the non-magnetic material layer is exposed; a fourth step of making a curved recess in the non-magnetic material layer by isotropically etching the non-magnetic material layer through the opening of the mask layer; a fifth step of making an approximately tapered recess down from the bottom of the curved recess by anisotropically etching the non-magnetic material layer through the opening of the mask layer; and a sixth step of making the upper write pole by burying a magnetic material in the tapered recess and the curved recess is provided.

Magnetic head manufacturing method

A method for manufacturing a magnetic head which includes a lower write pole having a projection, an upper write pole having a projection opposed to the projection of the lower write pole, and a magnetic gap interposed between the projection of the upper write pole and the projection of the upper write pole, comprising: a first step of making the magnetic gap on the projection of the lower write pole; a second step of making a non-magnetic material layer on the lower write pole, the non-magnetic material layer having a projection on its top surface in positional alignment with the projection of the lower write pole; a third step of making a mask layer on the non-magnetic material layer, the mask layer having an opening in which the top surface of the projection of the non-magnetic material layer is exposed; a fourth step of making a curved recess in the non-magnetic material layer by isotropically etching the non-magnetic material layer through the opening of the mask layer; a fifth step of making an approximately tapered recess down from the bottom of the curved recess by anisotropically etching the non-magnetic material layer through the opening of the mask layer; and a sixth step of making the upper write pole by burying a magnetic material in the tapered recess and the curved recess is provided.

A thin-film magnetic head comprises a magnetic gap disposed to be positioned on an air bearing surface of the magnetic head, a pair of magnetic poles disposed to hold the magnetic gap therebetween, and a coil positioned between the pair of the magnetic poles to intersect the magnetic poles, wherein at least one of the magnetic poles being composed of a T-shaped magnetic pole, the T-shaped magnetic pole comprising a front part of a magnetic pole contacting with the magnetic gap, an intermediate part of a magnetic pole lying on the front part, and a rear part of a magnetic pole lying on the intermediate part, wherein a width of the front part roughly defines a track width, the rear part has a wider width in a direction of track width than a width of the front part, and the intermediate part contacts with the rear part at an entire width of the rear part at the air bearing surface and has a narrower width at a contacting face with the front part than the width of the rear part.

Thin-film magnetic head having improved magnetic pole structure

A magnetic head has a recording/reproducing element which is embedded in an insulation layer made of an AlO.sub.x thin film and a leading end of which is positioned at a medium opposed face. A high-hardness coating layer or a high-thermal conductivity coating layer made of diamond-like carbon or the like is disposed on a peripheral region of the medium opposed face, excluding the leading end of the recording/reproducing element and a region in the neighborhood thereof. Even in the case where the magnetic head is applied to a magnetic disk apparatus of contact recording/reproducing system, it is possible to greatly restrain wear of the leading end of the recording/reproducing element and the region in the neighborhood thereof. Further, the heat dissipation characteristic of the leading end of the recording/reproducing element can be improved greatly. The dishing of the leading end of the recording/reproducing element can be reduced to a great extent by so etching the peripheral region of the medium opposed face that the leading end of the recording/reproducing element is projected; forming the high-hardness coating layer on an etched region; and processing the projected region by wear in a final process.

Magnetic head and method of manufacturing magnetic head

A composite magnetic head includes a recording head and a reproducing head. The recording head may be formed below or above the reproducing head. The lower of the recording and reproducing heads includes a first electrode. In addition, a conductive layer acting as a pole structure for the recording head includes a portion defining a hole through which a second electrode is made to contact the first electrode.

Growing community of inventors

Kanagawa-ken, Japan

Takeo Sakakubo