Hitachi, Ltd.

Hitachi Global Storage Technologies Netherlands B.v.

Hgst Netherlands, B.v.

Hitachi Global Storage Technologies Japan, Ltd.

Other

Nissan Motor Company Limited

Hitachi Global Storage Technologies

Tomohiro Okada

Isao Nunokawa

Masafumi Mochizuki

Kimitoshi Etoh

Hiroshi Fukui

Atsushi Nakamura

Yoshiaki Kawato

Hisashi Takano

Hisashi Kimura

Moriaki Fuyama

Yohji Maruyama

Naoki Koyama

Makoto Morijiri

Tadayuki Iwakura

Tetsuya Okai

Harunobu Saito

Shinobu Sasaki

Yasutaka Nishida

Matahiro Komuro

Takashi Kawabe

Miki Hara

Mikito Sugiyama

Tetsuo Ito

Atsushi Kato

Kaori Suzuki

Wataru Kimura

Kikuo Kusukawa

Masahiko Soga

Masafumi Michizuki

Hiroshi Fukuda

Hideaki Tanaka

Toshiki Kaneko

Ken Yoshioka

Kenchi Ito

Yoshihiro Shiroishi

Yimin Hsu

Hideki Saga

Masahiko Ando

Masatoshi Wakagi

Kenichi Onisawa

Yasuyuki Okada

Noboru Shimizu

Takayoshi Ohtsu

Katsumi Hoshino

Hiroaki Nemoto

Saburou Kanai

Nian Xiang Sun

Yinshi Liu

Kazuhiko Hosomi

Masaaki Sano

Yoji Maruyama

Ikuya Tagawa

Ken Nakayama

Ichiro Oodake

Taku Shintani

Hitoshi Harata

Yunxiao Gao

Tetsuroh Minemura

Kazuhiko Soeda

Shigeo Fujita

Yoshimi Torii

Yasuo Wakaki

Takahiro Saruwatari

Naoaki Oikawa

Tomoya Horide

Takehito Usui

Noboru Yoshida

Tutomu Yasuda

Tatsuhiko Ikeda

Tadashi Umezawa

Akinori Inada

Yuji Ueda

A power transmission device for a vehicle is comprised of a motor including a rotor shaft and a stator having an electromagnetic coil; an inverter configured to generate an alternating current, the inverter being connected with the coil to controllably rotate the rotor shaft relative to the stator; a gear set including an input shaft coupled with and rotated by the rotor shaft, an output shaft and gears so meshed as to transmit torque of the input shaft to the output shaft; and a grounding path electrically connecting a part of the gear set with a body of the vehicle, the part being so disposed as to have the input shaft electrically interposed between the part and the rotor shaft.

Gear system for electric vehicle

In one embodiment, a magnetic head includes a main pole configured to emit a recording magnetic field for affecting a magnetic medium, the main pole configured to serve as a first electrode and having a front portion at an air bearing surface (ABS) of the magnetic head and a rear portion extending from the front portion in an element height direction perpendicular to the ABS, wherein an upper surface of the front portion of the main pole is angled with respect to a plane of deposition at a first angle of inclination of greater than 0&#xb0;, and wherein at least a portion of an upper surface of the rear portion of the main pole is angled at a first angle of declination greater than 0&#xb0; with respect to the plane of deposition, an upper shield positioned above the main pole, the upper shield configured to serve as a second electrode, and a microwave oscillator positioned between the main pole and the upper shield at the ABS.

Microwave-assisted magnetic recording (MAMR) head with an inclined and recessed main pole structure

In one embodiment, a high-frequency magnetic field-assisted magnetic recording (MAMR) head includes: a yoke adapted for facilitating magnetic flux through the MAMR head; a main pole magnetically coupled to the yoke and adapted for producing a writing magnetic field; a return pole spaced from the main pole; a spin torque oscillator (STO) positioned above the main pole; and a back gap layer positioned between the yoke and the return pole, where at least one of the yoke, the main pole, the return pole, and the back gap layer comprises a highly resistive magnetic material.

Microwave-assisted magnetic recording (MAMR) head with highly resistive magnetic material

A head-slider. The head-slider includes a slider, and a thin-film magnetic-recording head. The thin-film magnetic-recording head includes: a read element; a write element; a non-magnetic insulating protective layer disposed around both read and write elements; a resist disposed at a position further away from an air-bearing surface than the read element; and, a hard-material member including a material selected from the group consisting of silicon carbide and tungsten, which is disposed at a position further away from the air-bearing surface than the read element and the write element. Both an end of the resist and an end of the hard-material member overlap the write element when viewed in a stacking direction. A ratio of a distance from the air-bearing surface to a deepest end of the hard-material member to a distance from the air-bearing surface to a deepest end of the resist is at least 0.9.

Head-slider including thin-film magnetic-recording head having reduced thermal protrusion

A magnetic storage apparatus includes a magnetic recording medium, a microwave assisted magnetic recording head at least equipped with a magnetic recording pole that generates a recording magnetic field for writing to the magnetic recording medium and a high-frequency oscillator that generates a high-frequency field, a magnetic reproducing head that reads information from the magnetic recording medium, a signal processing unit that processes a signal written by the magnetic recording head and a signal read by the magnetic reproducing head and a unit that controls clearance between the high-frequency oscillator and the magnetic recording medium. The magnetic storage apparatus has a characteristic that the high-frequency oscillator is not operated except in recording.

Magnetic storage apparatus, head drive controller, and head drive control method

Embodiments of the invention reduce the throat height of a single pole type head with high accuracy. In one embodiment, a head with an electro lapping guide for controlling a write head's throat height during air bearing surface processing is made. Air bearing surface processing is performed using the electro lapping guide. For a read head, processing is performed using the read head itself or an electro lapping guide for the read head so that both the throat height of write head and the element height of read head are controlled.

Magnetic head with electro lapping guide

A perpendicular recording magnetic head is provided, according to one embodiment, in which even if a thickness of a main pole is reduced corresponding to a reduction in a recording track width, recording performance is not degraded. A magnetic-field auxiliary pole and a nonmagnetic layer are stacked on a main pole, and a nonmagnetic portion is provided on each side face on a flying surface side of the magnetic-field auxiliary pole and the nonmagnetic layer, in one approach. In all regions except for a region near a flying surface, an interval between the main pole and a shield is increased by the nonmagnetic portion and the nonmagnetic layer, so that magnetic field loss is prevented, and consequently magnetic field strength and a magnetic field gradient are increased. Other systems and methods are also disclosed for retaining magnetic recording performance while reducing a thickness of a main pole.

Perpendicular recording magnetic head with a varying interval between the main pole and the shield, and methods of manufacturing thereof

An optically assisted magnetic recording head causes light to be efficiently incident on a near-field light generating element and is thereby capable of efficiently generating near-field light. The optically assisted magnetic recording head, according to one embodiment, has a waveguide and a thin metal film. The waveguide has a core and a clad at least partially surrounding the core and serves as near-field light generating device. The core has a plate-shaped portion that has a small width and protrudes from an edge of the core. The edge of the core is located on the air bearing surface side. The thin metal film is provided on an upper portion and side portions of the plate-shaped portion to cover the edge of the core at the air bearing surface side. Other systems and methods are disclosed as well to achieve efficient incident light on a near-field light generating element.

Optically assisted magnetic recording head having a waveguide core with a plate-shaped portion protruding from an air bearing surface side of the core

Embodiments of the invention provide a perpendicular magnetic recording head that causes the difference between a physical track width and an effective track width to be small. Sides of a main pole are made concave with the concave vertex on each side located close to a trailing edge of the main pole.

Perpendicular magnetic recording head

Embodiments of the invention are directed to narrowing a read/write gap of a perpendicular magnetic head by applying a wrap around shield, data erasing from return pole edges by returning recording field, and reducing TPR of a magnetic material. In one embodiment, the wrap around shields are formed by partitioning and making Gd, which is the height of the shield at the main pole side in the sensor height direction, smaller than the height of the shield connected to the return pole in the sensor height direction.

Magnetic recording head for perpendicular recording with wrap around shield, the fabrication process and magnetic disk storage apparatus mounting the magnetic head

Embodiments of the present invention help to provide a method for manufacturing a perpendicular magnetic recording head including a main magnetic pole having a width that does not generally vary. According to one embodiment, a magnetic film, a first inorganic mask film, an organic film, a second inorganic mask film, and a resist pattern are formed in this order. Reactive ion etching (RIE) is performed using the resist pattern as a mask to etch the second inorganic mask film and the organic film and form a mask for the subsequent step. A flow rate of an Ar gas is then controlled, and ion milling is performed, to correct a difference between the width of the mask located at the central portion of the wafer and the width of the mask located at the outer peripheral portion of the wafer. The magnetic film is processed to have a uniform track width. Ion milling is then performed to form the main magnetic pole having an inverted trapezoidal shape.

Method for manufacturing perpendicular magnetic recording head

An embodiment of the present invention relates to a method of manufacturing a perpendicular magnetic recording having a main pole, return pole and trailing side shield disposed on the trailing side and the cross track direction side of said main pole. A process is described where the main pole has an etching layer in the upper part. The top and sides of the main pole having the etching signal layer in the upper part are covered with a nonmagnetic gap layer while leaving open a region forming the side shield. The nonmagnetic gap layer is then etched until a signal from the etching signal layer is detected by an etching signal detector. The trailing side shield on the top and sides of the nonmagnetic gap layer are then formed after the etching is halted.

Method for manufacturing a perpendicular magnetic recording head

The main magnetic pole piece of a magnetic head for perpendicular magnetic recording preferably has an inverted trapezoidal shape in order to maintain a sufficient recording magnetic field. Embodiments of the present invention enhance the covering power of the protective film around the main magnetic pole piece of the magnetic head and thereby ensure reliability even when the main magnetic pole piece has such a shape. In one embodiment, the protective film for protecting the main magnetic pole piece is formed by a sputtering apparatus while applying a bias, or it is formed by a carousel type sputtering apparatus or the chemical vapor deposition (CVD) technique.

Method of fabricating a magnetic recording head for perpendicular recording with enhanced covering power

Embodiments of the invention provide a head which can prevent an external magnetic field form erasing a signal on the medium and whose main magnetic pole piece does not corrode during processing of the air bearing surface. In one embodiment, an anti-corrosion electrode is formed to apply a voltage to the main magnetic pole piece during processing of the air bearing surface. This retards corrosion of the main magnetic pole piece. Since a conductor (anti-corrosion wire) connected to this anti-corrosion electrode is made of a nonmagnetic material, concentration of an external magnetic field into the main magnetic pole piece can be suppressed. Consequently, since the magnetic leakage field emitted from the main magnetic pole piece is reduced, erasure of the signal on the medium can be prevented. In addition, since the anti-corrosion wire is connected to the upper core, this wire can be formed in the same wiring layer as a wire which connects the coil to a write terminal, resulting in a simplified manufacturing process.

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

Embodiments of the invention provide a perpendicular magnetic writing head with a suppressed effective track width to be written on a magnetic medium while increasing writing magnetic field gradient. In one embodiment a trailing side shield is disposed by way of a gap film to a main pole of a perpendicular writing magnetic head. A gap distance (Gt) on a trailing side of the main pole and a gap distance (Gs) on a lateral side of the main pole is defined as Gt&#x3c;Gt, and a thickness (Gd) from an air bearing surface of the shield is made equal to or less than a throat height. Alternatively, the thickness of Gd on the side of the main pole is reduced to less than that on the trailing side of the main pole. Further, for preventing defoliation of the shield upon fabrication of the air bearing surface, a thickness for a portion away from the main pole is increased.

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

Growing community of inventors

Kanagawa, Japan

Tomohiro Okada