Patents by Inventor Kimitoshi Etoh

Kimitoshi Etoh has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7990653
    Abstract: Embodiments in accordance with the present invention provide a perpendicular recording magnetic head whose dimensional dependency on the nonuniformity of magnetic field strength and distribution during manufacture is minimized, with narrowed tracks and without attenuation or erasure of adjacent track data while maintaining high magnetic field strength. According to one embodiment, a magnetic material (trailing/side shield) for creating a steep gradient of magnetic field strength is provided at a trailing side of a pole tip of a main magnetic pole piece and in a direction of the track width. The magnetic head is formed so that a gap (side gap length “gl”) between a side shield and a throat height portion of the pole tip progressively decreases with an increasing distance from an air-bearing surface, in a direction of an element height.
    Type: Grant
    Filed: April 27, 2007
    Date of Patent: August 2, 2011
    Assignee: Hitachi Global Storage Technologies Netherland BV
    Inventors: Masafumi Mochizuki, Shuji Nishida, Kimitoshi Etoh, Isao Nunokawa
  • Patent number: 7895732
    Abstract: 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.
    Type: Grant
    Filed: March 15, 2007
    Date of Patent: March 1, 2011
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Tomohiro Okada, Isao Nunokawa, Kimitoshi Etoh, Kikuo Kusukawa
  • Patent number: 7881012
    Abstract: Embodiments in accordance with the present invention provide a magnetic head in which broadening of the write-field distribution in the track-width direction can be decreased without reducing the write-field intensity. A main pole includes a pole tip having a part which provides the write track-width and a yoke part recessed from the air bearing surface in the element height direction, the pole tip including at least two magnetic films having different track-width directions, and the throat height at the trailing side being made smaller than the throat height at the leading side.
    Type: Grant
    Filed: February 15, 2007
    Date of Patent: February 1, 2011
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Masafumi Mochizuki, Kimitoshi Etoh, Youji Maruyama, Hiroshi Fukui
  • Patent number: 7848053
    Abstract: 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.
    Type: Grant
    Filed: February 15, 2007
    Date of Patent: December 7, 2010
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Masafumi Mochizuki, Kimitoshi Etoh, Yoji Maruyama, Hiroshi Fukui
  • Patent number: 7788795
    Abstract: A method for manufacturing a magnetic head that is effective for the suppression of thermal protrusion. The magnetic head includes SiO2, Si nitride, or Si oxide as a coil insulator having a low coefficient of thermal expansion and high workability. The coil insulator is arranged at a position away from the air bearing surface and the air bearing surface is made of alumina, making slider processing easy.
    Type: Grant
    Filed: September 11, 2006
    Date of Patent: September 7, 2010
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Kimitoshi Etoh, Hisako Takei, Masayuki Kurita, Yuji Kumazawa
  • Publication number: 20100157484
    Abstract: 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.
    Type: Application
    Filed: December 11, 2009
    Publication date: June 24, 2010
    Inventors: Kimitoshi Etoh, Mikito Sugiyama, Isao Nunokawa, Tomohiro Okada
  • Publication number: 20100149697
    Abstract: A recording head having a narrowed track has a high recording magnetic field strength and a high recording magnetic field gradient has certain problems which may be difficult to overcome. In one embodiment, a magnetic film, which overhangs from a track width, is provided on a trailing side of a region retracted from an ABS of a main pole facing a recording medium. Thereby, a magnetic field strength on the trailing side is increased so that a difference in distribution of magnetic field strength defined by a geometrical Bevel angle given to the main pole is increased. Consequently, writing performance of the main pole is improved while forming a large magnetic clearance angle with respect to an adjacent track and suppresses writing into an adjacent track when skew occurs. Other systems and methods are also disclosed regarding a head with a high recording magnetic field using an overhanging magnetic film.
    Type: Application
    Filed: December 11, 2009
    Publication date: June 17, 2010
    Inventors: Isao Nunokawa, Mikito Sugiyama, Kikuo Kusukawa, Kimitoshi Etoh
  • Patent number: 7684149
    Abstract: Embodiments of the invention provide a magnetic head which assures an improved format efficiency without increase in the magnetic field intensity applied at a read element. In one embodiment, a magnetic head incorporates a write head having a main pole and an auxiliary pole, and a read head having a read element between reader shields. An auxiliary shield as a magnetic body is provided between the main pole and reader shields or on the opposite side of the main pole with the reader shields between the main pole and the auxiliary shield.
    Type: Grant
    Filed: October 29, 2004
    Date of Patent: March 23, 2010
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Masafumi Mochizuki, Kaori Suzuki, Kimitoshi Etoh
  • Patent number: 7681303
    Abstract: Embodiments of the present invention provide a method of manufacturing a magnetic head slider, the method being adapted so that throat height of a main magnetic pole piece of a perpendicular recording magnetic head can be controlled with high accuracy. According to one embodiment, a first Electrical Lapping Guide element (ELG) is disposed on the same layer as a plated underlayer of a shield of one write head in a row bar, and other ELGs are disposed on the same layer as that of a main magnetic pole piece of another write head. Front end positions (Tops) are detected from changes in resistance values of the other ELGs and an ending position of lapping is calculated. Since the front end positions (Tops) of the other ELGs are accurate, it is possible to assign a correlation to throat height “Th” of the main magnetic pole piece and the resistance value of the first ELG by detecting this resistance value existing when the front end positions (Tops) are detected.
    Type: Grant
    Filed: August 30, 2007
    Date of Patent: March 23, 2010
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Akira Kondo, Koji Tanaka, Kimitoshi Etoh, Ichiro Oodake
  • Patent number: 7679862
    Abstract: Embodiments of the invention secure a sufficiently large magnetic field, and deter a protrusion phenomenon of a perpendicular magnetic recording head, causing a problem in implementing a low flying height, while solving problems such as erasure of information in peripheral tracks. In one embodiment, a main pole or a stacked body made up of the main pole, and an auxiliary pole is deposited over an underlayer formed on a substrate so as to be in contact with the underlayer. On top of the main pole or the stacked body, there is deposited a coil, a return pole, and a read element in that order, thereby fabricating a perpendicular magnetic recording head.
    Type: Grant
    Filed: November 14, 2005
    Date of Patent: March 16, 2010
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Kazuhiro Nakamoto, Kimitoshi Etoh, Masayuki Kurita
  • Patent number: 7619857
    Abstract: Embodiments of the invention provide a magnetic disk device which lowers the cost, maintains reliability by compensating the thermal dent or protuberance caused by a change in the environmental temperature, makes it possible to increase the recording density by decreasing the floating amount of the slider, to increase the capacity of the device or to decrease the size thereof. In one embodiment, a magnetic disk device comprises a magnetic disk, a magnetic head slider, and a drive unit for moving the magnetic head slider, wherein an air stream is generated between the magnetic disk that rotates and the magnetic head slider to effect the recording or the reproduction in a state where the magnetic head slider is floating. The magnetic head slider includes a slider substrate portion and a thin-film head portion that has recording and reproducing elements, a metal film, and an insulating film formed on the slider substrate portion and constituting a slider-floating plane along with the slider substrate portion.
    Type: Grant
    Filed: March 10, 2006
    Date of Patent: November 17, 2009
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Masayuki Kurita, Toshiya Shiramatsu, Kimitoshi Etoh, Takanori Yamazaki
  • Patent number: 7606006
    Abstract: Embodiments of the invention provide a write head for perpendicular recording in which the magnetic field intensity applied at a read element is reduced with larger write-field gradients and the distance between a write element and a read element is small. In one embodiment, a pair of magnetic bodies for shielding a read element are provided on the leading and trailing sides of the read element respectively and whichever one of the two shields is the longer in the length from the air bearing surface is shorter than the length up to the back contact position PBK at which a main pole and an auxiliary pole are connected.
    Type: Grant
    Filed: December 15, 2004
    Date of Patent: October 20, 2009
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Masafumi Mochizuki, Kaori Suzuki, Kimitoshi Etoh
  • Patent number: 7535675
    Abstract: Embodiments of the invention provide a thin film magnetic recording head that can reduce the round portion of the track restriction part of the main pole and has excellent track width accuracy, as well as its fabrication method. In one embodiment, the main pole is etched in the following three processes. (1) An ion beam is injected into the substrate at an angle of about 50°±20° while vibrating the substrate horizontally within a range of about ±(30° to 150°) in a reference direction in which the ion beam is oriented from the medium to the air bearing surface. (2) The ion beam is injected into the substrate at an angle of about 60°±20° while vibrating the substrate around a predetermined angle of about 90° to 135° from a direction in which the ion beam is oriented from the medium to the air bearing surface.
    Type: Grant
    Filed: January 27, 2005
    Date of Patent: May 19, 2009
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Hisashi Kimura, Nobuo Yoshida, Isao Nunokawa, Kimitoshi Etoh
  • Patent number: 7508631
    Abstract: In a magnetic disk device, cost reduction is designed by improving productivity, and increase in recording density and increase in capacity of the device or size reduction are designed with reliability being ensured. In one embodiment, a magnetic disk device has a magnetic disk arranged rotatably, a magnetic head slider arranged in a manner of facing a surface of the magnetic disk, and a driving device for moving the magnetic head slider in a radial direction of the surface of the magnetic disk. The magnetic head slider has a silicon slider-substrate-portion and a thin-film head portion which is formed on the slider substrate portion using a thin-film process and forms an air-bearing surface along with the slider substrate portion.
    Type: Grant
    Filed: September 30, 2005
    Date of Patent: March 24, 2009
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Kimitoshi Etoh, Masayuki Kurita, Tokuyama Mikio, Shiramatsu Toshiya
  • Publication number: 20080198507
    Abstract: Embodiments of the present invention help to suppress broadening of a write field of a main pole of a perpendicular recording head and realize high-quality write operation. According to one embodiment, a main pole of a write head extends to an air bearing surface or a medium-facing surface and has an inverted trapezoid in cross-section. First soft magnetic films called side shields are separately disposed through a nonmagnetic film on both sides of the main pole. The air bearing surface side end of the first soft magnetic film is provided to recede from the air bearing surface. The first soft magnetic film and the main pole are formed in the same layer. A second soft magnetic film called a trailing shield is provided above the main pole on the air bearing surface side via a nonmagnetic film.
    Type: Application
    Filed: February 15, 2008
    Publication date: August 21, 2008
    Inventors: Yoji Maruyama, Tadayuki Iwakura, Kimitoshi Etoh, Hiromi Shiina, Kazue Kudo
  • Patent number: 7389578
    Abstract: Embodiments in accordance with the present invention relate to methods wherein when a main pole is processed by using an ion milling technique, a re-adhesion layer created on the side face of the resist mask is removed with certainty. In one embodiment, an inorganic insulator from 5 nm to 100 nm which is soluble in an alkaline is arranged between the main pole material and a mask for processing the main pole material, and the main pole is processed by ion milling. After this process, the mask is peeled off, a surface treatment is performed by using an alkaline solution, resulting in the re-deposition film being removed.
    Type: Grant
    Filed: December 21, 2006
    Date of Patent: June 24, 2008
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Kimitoshi Etoh, Kikuo Kusukawa, Hisashi Kimura, Tomohiro Okada
  • Publication number: 20080072418
    Abstract: Embodiments of the present invention provide a method of manufacturing a magnetic head slider, the method being adapted so that throat height of a main magnetic pole piece of a perpendicular recording magnetic head can be controlled with high accuracy. According to one embodiment, a first Electrical Lapping Guide element (ELG) is disposed on the same layer as a plated underlayer of a shield of one write head in a row bar, and other ELGs are disposed on the same layer as that of a main magnetic pole piece of another write head. Front end positions (Tops) are detected from changes in resistance values of the other ELGs and an ending position of lapping is calculated. Since the front end positions (Tops) of the other ELGs are accurate, it is possible to assign a correlation to throat height “Th” of the main magnetic pole piece and the resistance value of the first ELG by detecting this resistance value existing when the front end positions (Tops) are detected.
    Type: Application
    Filed: August 30, 2007
    Publication date: March 27, 2008
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Akira Kondo, Koji Tanaka, Kimitoshi Etoh, Ichiro Oodake
  • Patent number: 7333301
    Abstract: A thin-film magnetic head having little temperature rise in the element, good heat dissipation and a short magnetic path length (narrow coil pitch) and manufacturing method for same is provided. To form the coil of the thin-film magnetic head, a lower coil is first formed and after forming alumina and an inorganic compound containing alumina, a trench is formed for the upper coil by reactive ion etching. The lower coil allows uniform etching at this time and functions as a film to prevent loading effects occurring during reactive ion etching. This trench is then plated in copper and chemical mechanical planarization performed to form the upper layer coil as the dual-layer coil of the present invention. Heat from the coil is efficiently radiated towards the substrate by alumina and an inorganic compound containing alumina with good heat propagation.
    Type: Grant
    Filed: August 29, 2003
    Date of Patent: February 19, 2008
    Assignee: Hitachi Global Storage Technologies Japan, Ltd.
    Inventors: Kimitoshi Etoh, Nobuo Yoshida, Moriaki Fuyama, Makoto Morijiri, Kenichi Meguro, Ichiro Oodake, Kazue Kudo, Yohji Maruyama, Katsuro Watanabe
  • Patent number: 7310203
    Abstract: There is provided a thin film magnetic head, with letting a distance of a portion, where a width of a track portion in an upper magnetic pole changes, from a flying plane from a medium be Ly, and letting a distance of a portion, where a distance between right and left of a surface portion in a lower magnetic pole in a track width direction is wider than the width of the upper magnetic pole in the track width direction, from the flying plane from a medium be Tp, by creating a thin film magnetic head that is equipped with a recording head that has a relation of Tp?Ly, it becomes possible to reduce a needless leakage magnetic field in the track width direction with securing magnetic field strength.
    Type: Grant
    Filed: September 10, 2002
    Date of Patent: December 18, 2007
    Assignee: Hitachi Global Storage Technologies Japan, Ltd.
    Inventors: Nobuo Yoshida, Ichiro Oodake, Moriaki Fuyama, Kazue Kudo, Kimitoshi Etoh, Shigekazu Ohtomo, Hiroshi Fukui
  • Publication number: 20070253107
    Abstract: Embodiments in accordance with the present invention provide a perpendicular recording magnetic head whose dimensional dependency on the nonuniformity of magnetic field strength and distribution during manufacture is minimized, with narrowed tracks and without attenuation or erasure of adjacent track data while maintaining high magnetic field strength. According to one embodiment, a magnetic material (trailing/side shield) for creating a steep gradient of magnetic field strength is provided at a trailing side of a pole tip of a main magnetic pole piece and in a direction of the track width. The magnetic head is formed so that a gap (side gap length “gl”) between a side shield and a throat height portion of the pole tip progressively decreases with an increasing distance from an air-bearing surface, in a direction of an element height.
    Type: Application
    Filed: April 27, 2007
    Publication date: November 1, 2007
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Masafumi Mochizuki, Shuji Nishida, Kimitoshi Etoh, Isao Nunokawa