Hitachi Global Storage Technologies Netherlands B.v.

Hitachi, Ltd.

Hitachi Global Storage Technologies Japan, Ltd.

Hgst Netherlands, B.v.

Yoji Maruyama

Masafumi Mochizuki

Hiroshi Fukui

Ichiro Ohdake

Atsushi Nakamura

Tadayuki Iwakura

Hisashi Takano

Yoshio Suzuki

Kimitoshi Etoh

Kazue Kudo

Ryoichi Nakatani

Makoto Morijiri

Shigekazu Ohtomo

Ryo Suzuki

Mikio Tokuyama

Tomohiro Okada

Hiroshi Ide

Takashi Toyooka

Hideki Zaitsu

Kazuo Nate

Kaori Suzuki

Teruyoshi Higashiya

Sadanori Nagaike

Tetsuya Okai

Makoto Aihara

Sunao Yonekawa

Hideki Sonobe

Tetsuji Higashijima

Akira Morinaga

Norifumi Miyamoto

Takayuki Iwakura

Masafumi Mochizuku

Embodiments in accordance with the present invention provide a magnetic head having a narrow track width and excellent in productivity for the purpose of realizing a disk storage unit having a large capacity. In a magnetic head having a plurality of flairs on a main magnetic pole, a side shield is formed via a non-magnetic film on both sides of the flair disposed close to an air bearing surface in such a fashion as to be aligned with the flair.

Perpendicular magnetic head with side shield depth less than write gap film

Embodiments in accordance with the present invention provide a magnetic head in which broadening of the effective track width can be decreased without reducing the write-field intensity and a variation of the track width can be decreased. A main pole consists of a pole tip having a part which provides the write track-width and a yoke part recessed from the air beating surface in the element height direction, and the pole tip consists of a pole tip at the trailing side where the width in the track-width direction is large and a pole tip at the leading side where the width in the track width direction is small. Moreover, the throat height of the pole tip at the trailing side is made greater than the throat height of the pole tip at the leading side.

Magnetic head and magnetic disk storage apparatus mounting the head

Embodiments of the invention provide a perpendicular magnetic head with a narrow track and excellent high frequency characteristics. In one embodiment, a recording magnetic head includes coil conductors and magnetic pole pieces putting the same therebetween, in which a main magnetic pole piece is formed into a planar structure and a magnetic film connected with the main magnetic pole piece in a magnetic coupling relation is curved in the direction of the film thickness. Further, a shield material disposed near the main magnetic pole piece is made of a material of higher resistance than that of the material for the read shield.

Perpendicular magnetic recording head for high frequency drive

In one embodiment, a thin-film magnetic head with a write head has a lower core member made of a soft magnetic film, a planar upper core member made of a soft magnetic film, and a coil conductor positioned between the lower and upper core members. The rear end is equipped with a magnetic body, which at least magnetically joins the lower and upper core members. A magnetic pole piece is in contact with the lower core member and positioned toward an air bearing surface, which faces a recording medium. A first nonmagnetic film is provided between a pedestal magnetic pole piece and upper core member. The write head is structured so that the first nonmagnetic film constitutes a write gap. A second nonmagnetic film is provided above or below the first nonmagnetic film. The edge of the second nonmagnetic film is retracted from the air bearing surface. The upper core member's flare point is positioned toward the air bearing surface rather than the edge of the second nonmagnetic film.

Magnetic write head including a magnetic pole piece having a protrusion

A magnetic head with a narrow track width angle and of excellent mass productivity is provided for attaining a large capacity magnetic disk drive. In an embodiment, a perpendicular recording magnetic head includes: a first non-magnetic film and a first soft magnetic film stacked on the trailing side of a main magnetic pole piece for constituting a gap film; a second non-magnetic layer in contact with the end face of the first non-magnetic layer on both sides of the main magnetic pole piece; a third soft magnetic film in contact with the second non-magnetic layer on both sides of the main magnetic pole piece; and a second soft magnetic film in contact with the first soft magnetic film and the third soft magnetic film on the trailing side of the main magnetic pole.

Main pole structure coupled with trailing gap for perpendicular recording

Embodiments of the invention provide a magnetic head (magnetic disk storage) which does not erase data on a recording medium even when a stray field is applied. In one embodiment, the head has a structure that d&#x3c;tand d&#x3c;tare satisfied where ddenotes the positional difference between edges of an auxiliary pole and an upper shield in the cross-track direction, ddenotes the positional difference between edges of the upper shield and a lower shield in the cross-track direction, tthe film thickness of the auxiliary pole or upper shield, whichever magnetic layer is larger in cross-track width, and tthe film thickness of the upper shield or lower shield, whichever magnetic layer is larger in cross-track width.

Magnetic head to prevent undesired data erasure and magnetic disk storage having the same

Embodiments of the invention provide a magnetic head which prevents data on a recording medium from being erased even when a stray field is applied. In one embodiment, a magnetic head includes a perpendicular write head having a main pole and an auxiliary pole; and a read head having a lower shield, an upper shield and a magneto-resistive element formed between the lower shield and the upper shield. At least one of the auxiliary pole, lower shield and upper shield has a recessed portion, whose height in an element height direction is lower than the height of edges thereof in a track width direction, on a surface opposite to the air bearing surface.

Magnetic head with recessed portion, and magnetic recording and reproduction apparatus comprising the same

A write head's material having a great thermal expansion coefficient expands due to Joule heat resulting from a write current and a temperature rise dependent on high-frequency core loss, thereby causing the head's flying surface to protrude toward a magnetic disk. This phenomenon is called TPR (thermal protrusion). It is essential that the flying height be accurately determined and managed in consideration of TPR. A magnetic disk drive for actual use or a magnetic disk drive that is in a testing process but similar to the one for actual use is used to measure TPR amount changes resulting from a write operation, store the resulting measured data in a memory or on the magnetic disk, and perform flying height management with the stored measured data. Further, flying height management is performed as needed in conjunction with a SMART function. The present invention makes it possible to perform high-reliability flying height management.

Magnetic disk drive having a function for using a thermal protrusion amount for flying height management and an inspection device having such a function

A magnetic head is composed to diminish disordered writing bits of a recording layer or reading noise caused by a magnetic field generated from an under layer without decreasing a writing magnetic field strength of the magnetic head. The magnetic head includes a write head provided with a main pole and one or more auxiliary poles, a read head provided with a read element, and coils located on both sides of the main pole in a manner to sandwich the main pole. The coil located on one side generates the asymmetrical magneto-motive force for magnetizing the main pole to that generated by the coil located on the other side.

Magnetic head for perpendicular recording and magnetic disk storage apparatus mounting the head

A magnetic material having a low coefficient of thermal expansion of 11.5&#xd7;10/K or less is used for forming at least one of a lower shield or an upper shield. A laminated film comprising a layer of the magnetic material having a low coefficient of thermal expansion of 11.5&#xd7;10/K or less, and an 80 wt % NiFe alloy layer, is used for forming at least one of the lower shield and the upper shield. Thus, the thin film magnetic head having reduced after-record noise and reduced thermal protrusion can be obtained.

Thin film magnetic head

The present invention is to provide a thin film magnetic head intended to increase precision of and to narrow a width which determines a track width of a write thin film magnetic head and to supply a stably high output substantially free from write blurring on a disk, and a method for manufacturing the same. The thin film magnetic head consisting of a magnetic circuit comprising a read head to read information, a lower magnetic film, a magnetic gap and an upper magnetic film formed with a magnetic gap between it and the lower magnetic film; and of a write head comprising a coil positioned between the upper magnetic film and the lower magnetic film and an insulating film for insulting the coil and the upper magnetic film from each other, wherein the upper magnetic film is configured of an upper first magnetic film, an upper second magnetic film and an upper third magnetic film, and the upper first magnetic film is connected to the upper third magnetic film via the upper second magnetic film.

Thin film magnetic head having multiple layered films determining track width imbedded in an insulating film and method of manufacturing the same

It is the object of the invention to provide a magnetic head and a magnetic storage apparatus using the magnetic head provided with a signal reproducing means which is capable of using the same signal processing circuit as used for the conventional longitudinal magnetization film type recording medium even when a perpendicular magnetization film type recording medium is used. Because the present invention renders the reproducing signal generated from a perpendicular magnetization film Gaussian shaped (Lorentzian pulse), the same signal processing circuit as used for the conventional longitudinal magnetization film type recording medium can be used. To accomplish this object, in the reproducing means which is the component of the information reproducing component of the magnetic head, the first spin valve element and the second valve element are piled up, the magnetization direction of pinned layers of both elements is prescribed so as to be antiparallel each other, and lead electrodes of both elements are connected so as to be common. When two spin valve elements are piled up to compose a reproducing means, the first spin valve element is structured so as to have an Ru film between the first ferromagnetic film and the second ferromagnetic film and so as to have a Cu film between the second ferromagnetic film and the third ferromagnetic film, and the second spin valve element is structured so as to have a Cu film between the fourth ferromagnetic film and the fifth ferromagnetic film. These two elements are piled up with interposition of a desired spacer film adjacently.

Magnetic head and magnetic storage apparatus using the same

It is the object of the invention to provide a magnetic head and a magnetic storage apparatus using the magnetic head provided with a signal reproducing means which is capable of using the same signal processing circuit as used for the conventional longitudinal magnetization film type recording medium even when a perpendicular magnetization film type recording medium is used. Because the present invention renders the reproducing signal generated from a perpendicular magnetization film Gaussian shaped (Lorentizian pulse), the same signal processing circuit as used for the conventional longitudinal magnetization film type recording medium can be used. To accomplish this object, in the reproducing means which is the component of the information reproducing component of the magnetic head, the first spin valve element and the second valve element are piled up, the magnetization direction of pinned layers of both elements is prescribed so as to be antiparallel each other, and lead electrodes of both elements are connected so as to be common.

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Saitama, Japan

Yoji Maruyama