Patents by Inventor Tadayuki Iwakura
Tadayuki Iwakura 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).
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Patent number: 9230566Abstract: Embodiments disclosed herein generally relate to a perpendicular magnetic recording head for recording magnetic information and a magnetic recording device employing the magnetic head. The magnetic recording head comprises at least one thin shield region having a high coercive force and a magnetization direction oriented towards the right when viewed from the MFS with the leading side on bottom and the trailing side on top, and at least one thick shield region having a low coercive force. The thin shield region surrounds a main pole, and the thick shield region partially surrounds the thin shield region. The magnetic recording head is able to reduce FTI by controlling the magnetization direction of the shield layers.Type: GrantFiled: October 29, 2014Date of Patent: January 5, 2016Assignee: HGST Netherlands B.V.Inventors: Tadayuki Iwakura, Yohji Maruyama, Wataru Kimura, Shigeru Tadokoro
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Patent number: 8542462Abstract: According to one embodiment, a perpendicular magnetic recording head includes a main magnetic pole having a trailing side and two lateral sides, a magnetic shield near the trailing side and both lateral sides of the main magnetic pole, the magnetic shield comprising: a first soft magnetic film with a relatively high saturation flux density positioned facing depthwise from a floating surface side thereof, a second soft magnetic film with a relatively low saturation flux density, and a first non-magnetic film. The head also includes a non-magnetic film interposed between the magnetic shield and the main magnetic pole, a first magnetic film magnetically coupled to the magnetic shield and the main magnetic pole on a side opposite a floating surface side thereof, and a coil surrounding a magnetic circuit, the magnetic circuit comprising the main magnetic pole and the first magnetic film. Other systems and methods are also described.Type: GrantFiled: June 30, 2010Date of Patent: September 24, 2013Assignee: HGST Netherlands B.V.Inventors: Yohji Maruyama, Tadayuki Iwakura, Tetsuya Okai, Hiromi Shiina, Kazue Kudo
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Patent number: 8300358Abstract: 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: GrantFiled: February 15, 2008Date of Patent: October 30, 2012Assignee: Hitachi Global Storage Technologies Netherlands B.V.Inventors: Yohji Maruyama, Tadayuki Iwakura, Kimitoshi Etoh, Hiromi Shiina, Kazue Kudo
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Patent number: 8054580Abstract: Embodiments of the present invention provide a perpendicular recording magnetic head having a narrow track width, high recording magnetic field intensity, and a good recording magnetic field distribution. According to one embodiment, a perpendicular recording magnetic head includes a read section and a write section. The write section includes a main magnetic pole layer, a lower sub magnetic pole layer, an upper sub magnetic pole layer, a pedestal magnetic layer, and a coil conductor generating a magnetic flux in the main magnetic pole layer. The write section further includes lower and upper auxiliary magnetic pole layers disposed on a leading side and a trailing side, respectively, relative to a medium moving direction, adjacent to the main magnetic pole layer. The lower and upper auxiliary magnetic pole layers are retracted from an air bearing surface. The upper auxiliary magnetic pole layer is retracted from the air bearing surface less than the lower auxiliary magnetic pole layer.Type: GrantFiled: March 24, 2008Date of Patent: November 8, 2011Assignee: Hitachi Gloabl Storage Technologies Netherlands B.V.Inventors: Wataru Kimura, Tadayuki Iwakura, Yohji Marujama
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Patent number: 8000058Abstract: Embodiments of the invention provide a perpendicular recording magnetic head capable of reducing leakage magnetic fields from the soft magnetic films on the air bearing surface side and reducing the protrusion of the soft magnetic films in the direction of the air bearing surface side due to thermal deformation of the soft magnetic films. In one embodiment, the write functional section includes a coil conductor, second soft magnetic film pattern and first soft magnetic film pattern that cover the coil conductor from top and bottom and are magnetically coupled to each other, and a main magnetic pole piece determining a track width. The read functional section includes a reading element sandwiched between two magnetic shield films. A pedestal magnetic pole pattern is formed at the frontal end position of the first soft magnetic film pattern.Type: GrantFiled: October 24, 2005Date of Patent: August 16, 2011Assignee: Hitachi Global Storage Technologies Netherlands B.V.Inventors: Tadayuki Iwakura, Youji Maruyama, Masafumi Mochizuki, Ichiro Ohdake
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Publication number: 20110002063Abstract: According to one embodiment, a perpendicular magnetic recording head includes a main magnetic pole having a trailing side and two lateral sides, a magnetic shield near the trailing side and both lateral sides of the main magnetic pole, the magnetic shield comprising: a first soft magnetic film with a relatively high saturation flux density positioned facing depthwise from a floating surface side thereof, a second soft magnetic film with a relatively low saturation flux density, and a first non-magnetic film. The head also includes a non-magnetic film interposed between the magnetic shield and the main magnetic pole, a first magnetic film magnetically coupled to the magnetic shield and the main magnetic pole on a side opposite a floating surface side thereof, and a coil surrounding a magnetic circuit, the magnetic circuit comprising the main magnetic pole and the first magnetic film. Other systems and methods are also described.Type: ApplicationFiled: June 30, 2010Publication date: January 6, 2011Inventors: Yohji Maruyama, Tadayuki Iwakura, Tetsuya Okai, Hiromi Shiina, Kazue Kudo
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Publication number: 20090290257Abstract: To enable high density recording, improvements to the distribution of the magnetic field originating from a perpendicular recording magnetic head with a narrow track width, high resolution, and narrow erase width were made. According to one embodiment, a perpendicular recording magnetic head is provided with a write head which comprises a main pole layer, an auxiliary pole layer, a first subsidiary pole layer, a second subsidiary pole layer, a pedestal-like soft magnetic layer and a coil. Trailing and leading throat heights are controlled so as to make the trailing throat height shorter than the leading throat height wherein the trailing throat height is the throat height of the main pole layer's medium-tracking trailing side (top side as viewed in the film thickness direction) while the leading throat height is the throat height of the main pole layer's medium-tracking leading side (bottom side as viewed in the film thickness direction).Type: ApplicationFiled: May 20, 2009Publication date: November 26, 2009Inventors: Wataru Kimura, Tadayuki Iwakura, Yoji Maruyama
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Patent number: 7576952Abstract: 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.Type: GrantFiled: September 30, 2004Date of Patent: August 18, 2009Assignee: Hitachi Global Storage Technologies Netherlands B.V.Inventors: Yoji Maruyama, Tadayuki Iwakura, Makoto Morijiri, Shigekazu Ohtomo, Ichiro Ohdake
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Patent number: 7551395Abstract: 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.Type: GrantFiled: July 24, 2006Date of Patent: June 23, 2009Assignee: Hitachi Global Storage Technologies Netherlands B.V.Inventors: Yoji Maruyama, Kazue Kudo, Ichiro Ohdake, Tadayuki Iwakura
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Patent number: 7460335Abstract: A magnetic head comprises a retrieving unit for converting magnetic information output from a recording medium into an electric signal, a writing unit having the function of electromagnetic conversion for writing the magnetic information in the recording medium in response to the electric signal, and a first protective film formed on the retrieving unit. A second protective film is formed on the first protective film. The coefficient of linear expansion of the second protective film is reduced in comparison with that of the first protective film. Furthermore, the first protective film is an alumina film; in contrast, the second protective film is a film made of an alumina film containing silicon oxide therein.Type: GrantFiled: May 1, 2006Date of Patent: December 2, 2008Assignee: Hitachi Global Technologies Japan, Ltd.Inventors: Yohji Maruyama, Tadayuki Iwakura, Takashi Kawabe, Makoto Morijiri, Hiroshi Fukui
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Publication number: 20080231994Abstract: Embodiments of the present invention provide a perpendicular recording magnetic head having a narrow track width, high recording magnetic field intensity, and a good recording magnetic field distribution. According to one embodiment, a perpendicular recording magnetic head includes a read section and a write section. The write section includes a main magnetic pole layer, a lower sub magnetic pole layer, an upper sub magnetic pole layer, a pedestal magnetic layer, and a coil conductor generating a magnetic flux in the main magnetic pole layer. The write section further includes lower and upper auxiliary magnetic pole layers disposed on a leading side and a trailing side, respectively, relative to a medium moving direction, adjacent to the main magnetic pole layer. The lower and upper auxiliary magnetic pole layers are retracted from an air bearing surface. The upper auxiliary magnetic pole layer is retracted from the air bearing surface less than the lower auxiliary magnetic pole layer.Type: ApplicationFiled: March 24, 2008Publication date: September 25, 2008Inventors: Wataru Kimura, Tadayuki Iwakura, Yoji Maruyama
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Publication number: 20080198507Abstract: 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: ApplicationFiled: February 15, 2008Publication date: August 21, 2008Inventors: Yoji Maruyama, Tadayuki Iwakura, Kimitoshi Etoh, Hiromi Shiina, Kazue Kudo
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Patent number: 7382576Abstract: Disclosed is a magnetic disk apparatus including a magnetic reproducing head portion, and a magnetic recording head including an upper magnetic core having a end portion and a rear portion. As a resist for a frame which is used for forming the rear portion, a negative resist or an electron beam resist is used, whereby the frame is formed without any adverse effect of halation from a coil insulating film. That is, it is possible to manufacture a magnetic recording head in which the rear portion of an upper magnetic core is not emerged at the face opposed to a medium, and hence to obtain a magnetic disk apparatus exhibiting an areal recording density of 5 Gbit/in2 or more by mounting a magnetic recording/reproducing head including such a magnetic recording head.Type: GrantFiled: May 4, 2006Date of Patent: June 3, 2008Assignee: Hitachi Global Storage Technologies Japan, Ltd.Inventors: Tomohiro Okada, Tetsuya Okai, Shinobu Sasaki, Tadayuki Iwakura, Naoki Koyama, Takashi Kawabe, Harunobu Saito, Makoto Morijiri
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Patent number: 7262940Abstract: A separate read/write magnetic head of the present invention includes a magnetoresistive head 11 having a magnetoresistive film 25 disposed between a lower shield 23 and an upper shield 28, both of which are formed on a substrate 21, and a pair of electrodes 26 electrically connected to the magnetoresistive film 25; and an inductive magnetic thin film head 12 having a coil 33 between a lower pole piece 31 and an upper pole piece 35, both of which are disposed on the upper shield 28 of the magnetoresistive head 11 with a separation film 29 being sandwiched therebetween, and through a magnetic gap film 32 and an interlayer insulating film 34. Reduced protrusion of the read head element toward the air bearing surface due to heat deformation caused by changes in ambient temperature can be achieved by configuring the lower shield 23 and the upper shield 28 so that the sum of their thicknesses is 0.4 ?m or more and less than 3.4 ?m.Type: GrantFiled: February 12, 2004Date of Patent: August 28, 2007Assignee: Hitachi Global Storage Technologies Japan, Ltd.Inventors: Tadayuki Iwakura, Youji Maruyama
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Publication number: 20070019327Abstract: 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.Type: ApplicationFiled: July 24, 2006Publication date: January 25, 2007Applicant: Hitachi Global Storage Technologies Netherlands B.V.Inventors: Yoji Maruyama, Kazue Kudo, Ichiro Ohdake, Tadayuki Iwakura
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Publication number: 20060198056Abstract: A magnetic head comprises a retrieving unit for converting magnetic information output from a recording medium into an electric signal, a writing unit having the function of electromagnetic conversion for writing the magnetic information in the recording medium in response to the electric signal, and a first protective film formed on the retrieving unit. A second protective film is formed on the first protective film. The coefficient of linear expansion of the second protective film is reduced in comparison with that of the first protective film. Furthermore, the first protective film is an alumina film; in contrast, the second protective film is a film made of an alumina film containing silicon oxide therein.Type: ApplicationFiled: May 1, 2006Publication date: September 7, 2006Applicant: Hitachi Global Storage Technologies Japan, Ltd.Inventors: Yohji Maruyama, Tadayuki Iwakura, Takashi Kawabe, Makoto Morijiri, Hiroshi Fukui
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Publication number: 20060198051Abstract: Disclosed is a magnetic disk apparatus including a magnetic reproducing head portion, and a magnetic recording head including an upper magnetic core having a end portion and a rear portion. As a resist for a frame which is used for forming the rear portion, a negative resist or an electron beam resist is used, whereby the frame is formed without any adverse effect of halation from a coil insulating film. That is, it is possible to manufacture a magnetic recording head in which the rear portion of an upper magnetic core is not emerged at the face opposed to a medium, and hence to obtain a magnetic disk apparatus exhibiting an areal recording density of 5 Gbit/in2 or more by mounting a magnetic recording/reproducing head including such a magnetic recording head.Type: ApplicationFiled: May 4, 2006Publication date: September 7, 2006Inventors: Tomohiro Okada, Tetsuya Okai, Shinobu Sasaki, Tadayuki Iwakura, Naoki Koyama, Harunobu Saito, Makoto Morijiri
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Patent number: 7068467Abstract: Disclosed is a magnetic disk apparatus including a magnetic reproducing head portion, and a magnetic recording head including an upper magnetic core having a end portion and a rear portion. As a resist for a frame which is used for forming the rear portion, a negative resist or an electron beam resist is used, whereby the frame is formed without any adverse effect of halation from a coil insulating film. That is, it is possible to manufacture a magnetic recording head in which the rear portion of an upper magnetic core is not emerged at the face opposed to a medium, and hence to obtain a magnetic disk apparatus exhibiting an areal recording density of 5 Gbit/in2 or more by mounting a magnetic recording/reproducing head including such a magnetic recording head.Type: GrantFiled: September 3, 2004Date of Patent: June 27, 2006Assignee: Hitachi Global Storage Technologies Japan, Ltd.Inventors: Tomohiro Okada, Tetsuya Okai, Shinobu Sasaki, Tadayuki Iwakura, Naoki Koyama, Harunobu Saito, Makoto Morijiri
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Patent number: 7064925Abstract: A magnetic head comprises a retrieving unit for converting magnetic information output from a recording medium into an electric signal, a writing unit having the function of electromagnetic conversion for writing the magnetic information in the recording medium in response to the electric signal, and a first protective film formed on the retrieving unit. A second protective film is formed on the first protective film. The coefficient of linear expansion of the second protective film is reduced in comparison with that of the first protective film. Furthermore, the first protective film is an alumina film; in contrast, the second protective film is a film made of an alumina film containing silicon oxide therein.Type: GrantFiled: September 5, 2003Date of Patent: June 20, 2006Assignee: Hitachi Global Storage Technologies Japan, Ltd.Inventors: Yohji Maruyama, Tadayuki Iwakura, Takashi Kawabe, Makoto Morijiri, Hiroshi Fukui
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Patent number: 7061726Abstract: A magnetic material having a low coefficient of thermal expansion of 11.5×10?6/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 11.5×10?6/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.Type: GrantFiled: September 18, 2003Date of Patent: June 13, 2006Assignee: Hitachi Global Storage Technologies Japan, Ltd.Inventors: Shigekazu Ohtomo, Hiroshi Fukui, Sunao Yonekawa, Yoji Maruyama, Tadayuki Iwakura