Patents by Inventor Michitaka Nishiyama

Michitaka Nishiyama 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: 10839829
    Abstract: A magnetic head includes a medium facing surface, a coil, a main pole, and a substrate. The main pole includes a first layer, and a second layer lying on the first layer. The first layer includes a thickness-changing portion whose dimension in a direction perpendicular to a top surface of the substrate decreases with decreasing distance to the medium facing surface. At least part of the second layer is located on the thickness-changing portion.
    Type: Grant
    Filed: September 27, 2019
    Date of Patent: November 17, 2020
    Assignee: HEADWAY TECHNOLOGIES, INC.
    Inventors: Yoshitaka Sasaki, Hiroyuki Ito, Kazuki Sato, Shigeki Tanemura, Tetsuya Roppongi, Kei Hirata, Atsushi Yamaguchi, Michitaka Nishiyama
  • Publication number: 20170337940
    Abstract: A manufacturing method for a magnetic head forms a leading shield having a top surface. The top surface of the leading shield includes first and second portions. The second portion is located farther from a medium facing surface than is the first portion, and recessed from the first portion. A first gap layer is then formed on the first portion. Then, a magnetic layer including an initial first side shield, an initial second side shield and a coupling section connecting them is formed using a mold. The mold is then removed. The coupling section is then removed by etching the magnetic layer. A second gap layer and a main pole are then formed in this order.
    Type: Application
    Filed: May 23, 2016
    Publication date: November 23, 2017
    Applicant: TDK CORPORATION
    Inventors: Hiroki ARITOMO, Atsushi YAMAGUCHI, Michitaka NISHIYAMA, Yumiko YOKOYAMA, Koichi OTANI
  • Patent number: 9824700
    Abstract: A manufacturing method for a magnetic head forms a leading shield having a top surface. The top surface of the leading shield includes first and second portions. The second portion is located farther from a medium facing surface than is the first portion, and recessed from the first portion. A first gap layer is then formed on the first portion. Then, a magnetic layer including an initial first side shield, an initial second side shield and a coupling section connecting them is formed using a mold. The mold is then removed. The coupling section is then removed by etching the magnetic layer. A second gap layer and a main pole are then formed in this order.
    Type: Grant
    Filed: May 23, 2016
    Date of Patent: November 21, 2017
    Assignee: TDK CORPORATION
    Inventors: Hiroki Aritomo, Atsushi Yamaguchi, Michitaka Nishiyama, Yumiko Yokoyama, Koichi Otani
  • Patent number: 9741371
    Abstract: A magnetic head includes a main pole, a write shield and a gap section. The write shield includes a trailing shield, a leading shield and two side shields. The gap section includes a trailing gap section, a leading gap section and two side gap sections. Each of the two side gap sections and the leading gap section increases in thickness with increasing distance from a medium facing surface. In the medium facing surface, the thickness of the leading gap section is greater than the width of each of the two side gap sections, and the width of each of the two side gap sections decreases with decreasing distance to the leading gap section.
    Type: Grant
    Filed: March 24, 2015
    Date of Patent: August 22, 2017
    Assignee: TDK CORPORATION
    Inventors: Atsushi Yamaguchi, Michitaka Nishiyama, Kei Hirata, Kenkichi Anagawa
  • Patent number: 9589582
    Abstract: A PMR writer is disclosed wherein a hot seed layer (HS) made of a 19-24 kilogauss (kG) magnetic material is formed between a gap layer and a 10-16 kG magnetic layer in the side shields, and between the leading gap and a 16-19 kG magnetic layer in the leading shield to improve the track field gradient and cross-track field gradient while maintaining write-ability. The HS is from 10 to 100 nm thick and has a first side facing the write pole with a height of ?0.15 micron, and a second side facing a main pole flared side that may extend to a full side shield height of ?0.5 micron. The trailing shield has a second hot seed layer on the write gap and a 16-19 kG magnetic layer that contacts the 10-16 kG side shield magnetic layer thereby forming an all wrap around (AWA) shield configuration.
    Type: Grant
    Filed: May 23, 2016
    Date of Patent: March 7, 2017
    Assignees: Headway Technologies, Inc., TDK Corporation
    Inventors: Yue Liu, Atsushi Yamaguchi, Yuhui Tang, Jiun-Ting Lee, Yaguang Wei, Xiaomin Liu, Hideyuki Ukita, Moris Dovek, Michitaka Nishiyama
  • Publication number: 20160307586
    Abstract: A PMR writer is disclosed wherein a hot seed layer (HS) made of a 19-24 kilogauss (kG) magnetic material is formed between a gap layer and a 10-16 kG magnetic layer in the side shields, and between the leading gap and a 16-19 kG magnetic layer in the leading shield to improve Hy_grad and Hy_grad_x while maintaining write-ability. The HS is from 10 to 100 nm thick and has a first side facing the write pole with a height of ?0.15 micron, and a second side facing a main pole flared side that may extend to a full side shield height of ?0.5 micron. First and second sides may form a continuous curve or a double tapered design where first and second sides have different angles with respect to a center plane. The side shield design described herein is especially beneficial for side gaps of 20-60 nm.
    Type: Application
    Filed: May 23, 2016
    Publication date: October 20, 2016
    Inventors: Yue Liu, Atsushi Yamaguchi, Yuhui Tang, Jiun-Ting Lee, Yaguang Wei, Xiaomin Liu, Hideyuki Ukita, Moris Dovek, Michitaka Nishiyama
  • Publication number: 20160284366
    Abstract: A magnetic head includes a main pole, a write shield and a gap section. The write shield includes a trailing shield, a leading shield and two side shields. The gap section includes a trailing gap section, a leading gap section and two side gap sections. Each of the two side gap sections and the leading gap section increases in thickness with increasing distance from a medium facing surface. In the medium facing surface, the thickness of the leading gap section is greater than the width of each of the two side gap sections, and the width of each of the two side gap sections decreases with decreasing distance to the leading gap section.
    Type: Application
    Filed: March 24, 2015
    Publication date: September 29, 2016
    Inventors: Atsushi YAMAGUCHI, Michitaka NISHIYAMA, Kei HIRATA, Kenkichi ANAGAWA
  • Patent number: 9361912
    Abstract: A PMR writer is disclosed wherein a hot seed layer (HS) made of a 19-24 kilogauss (kG) magnetic material is formed between a side gap and a 10-16 kG magnetic layer in the side shields, and between a 16-19 kG magnetic layer and the leading gap in the leading shield to improve Hy_grad and Hy_grad_x while maintaining write-ability. The HS is from 10 to 100 nm thick and has a first side facing the write pole with a height of ?0.15 micron, and a second side facing a main pole flared side that may extend to a full side shield height of ?0.5 micron. First and second sides may form a continuous curve or the a double tapered design where first and second sides have different angles with respect to a center plane. The side shield design described herein is especially beneficial for side gaps of 20-60 nm.
    Type: Grant
    Filed: April 20, 2015
    Date of Patent: June 7, 2016
    Assignees: Headway Technologies, Inc., TDK Corporation
    Inventors: Yue Liu, Atsushi Yamaguchi, Yuhui Tang, Jiun-Ting Lee, Yaguang Wei, Xiaomin Liu, Hideyuki Ukita, Moris Dovek, Michitaka Nishiyama
  • Patent number: 9153253
    Abstract: The perpendicular magnetic recording head includes: a magnetic pole including an end surface exposed on an air bearing surface, and extending in a height direction perpendicular to the air bearing surface; a leading shield including an end surface exposed on the air bearing surface; a leading gap provided between the magnetic pole and the leading shield; and a recess shield including a mid-part and other parts, and provided at a position on a side opposite to the magnetic pole with the leading shield in between, the mid-part being distanced from the leading shield in a track width direction, the other parts being in contact with the leading shield, and the position being recessed from the air bearing surface.
    Type: Grant
    Filed: January 8, 2014
    Date of Patent: October 6, 2015
    Assignee: TDK CORPORATION
    Inventors: Atsushi Yamaguchi, Atsushi Matsuo, Yuji Matsuura, Michitaka Nishiyama, Yumiko Yokoyama
  • Patent number: 9082432
    Abstract: A thin film magnetic head has a main magnetic pole layer; a first trailing shield that is positioned at the trailing side of the main magnetic pole layer, and that is close to the main magnetic pole layer; and a second trailing shield that is positioned at the trailing side of the first trailing shield, and that continues to the first trailing shield. An end surface of the second trailing shield positioned at the back side in the height direction has a first end side positioned at a medium opposing surface side, and a second end side positioned at the further back side in the height direction than the first end side, and at the trailing side closer than the first end side. An angle formed by a plane including the first end side and the second end side and a plane parallel to both the height direction and the track width direction is 30 degrees to 60 degrees.
    Type: Grant
    Filed: August 25, 2014
    Date of Patent: July 14, 2015
    Assignee: TDK Corporation
    Inventors: Yuji Matsuura, Atsushi Yamaguchi, Michitaka Nishiyama, Yumiko Yokoyama, Yuki Nishimura, Ittetsu Kitajima
  • Publication number: 20150194169
    Abstract: The perpendicular magnetic recording head includes: a magnetic pole including an end surface exposed on an air bearing surface, and extending in a height direction perpendicular to the air bearing surface; a leading shield including an end surface exposed on the air bearing surface; a leading gap provided between the magnetic pole and the leading shield; and a recess shield including a mid-part and other parts, and provided at a position on a side opposite to the magnetic pole with the leading shield in between, the mid-part being distanced from the leading shield in a track width direction, the other parts being in contact with the leading shield, and the position being recessed from the air bearing surface.
    Type: Application
    Filed: January 8, 2014
    Publication date: July 9, 2015
    Applicant: TDK CORPORATION
    Inventors: Atsushi YAMAGUCHI, Atsushi MATSUO, Yuji MATSUURA, Michitaka NISHIYAMA, Yumiko YOKOYAMA
  • Patent number: 8559133
    Abstract: A perpendicular magnetic write head includes: a magnetic pole having an end face on an air bearing surface; and side shield layers each having an end face on the air bearing surface, and arranged on both sides, in a write track width direction, of the magnetic pole with a side gap in between. The end face of the magnetic pole has a geometry in which a width at a trailing edge is larger than a width at a leading edge. Relationship D1<D2, D1<D3, and D3?D2 are satisfied in the air bearing surface, where D1 is a gap length of the side gap at the trailing edge, D2 is a gap length of the side gap at the leading edge, and D3 is a gap length of the side gap at any position between the trailing edge and the leading edge.
    Type: Grant
    Filed: June 1, 2009
    Date of Patent: October 15, 2013
    Assignee: TDK Corporation
    Inventors: Kei Hirata, Takeo Kagami, Tatsuhiro Nojima, Hisayoshi Watanabe, Michitaka Nishiyama
  • Patent number: 8472137
    Abstract: The present invention relates to a magnetic head, a manufacturing method therefor, a head assembly, and a magnetic recording/reproducing apparatus. According to the present invention, it includes a magnetic pole layer, a non-magnetic layer, a trailing gap layer, and a trailing shield layer. The magnetic pole layer has a pole tip exposed on a magnetic medium-facing surface. The non-magnetic layer is laid on the magnetic pole layer. The trailing shield layer is exposed on the magnetic medium-facing surface and laid over the magnetic pole layer and the non-magnetic layer with the trailing gap layer between. The magnetic pole layer and the non-magnetic layer have a continuous tapered face opposed to a lower side of the trailing shield layer. Moreover, the tapered face extends from a trailing edge of the pole tip at a constant inclination angle.
    Type: Grant
    Filed: July 28, 2010
    Date of Patent: June 25, 2013
    Assignee: TDK Corporation
    Inventors: Kei Hirata, Kenkichi Anagawa, Michitaka Nishiyama, Hideyuki Yatsu, Shin Narushima, Hisayoshi Watanabe, Tatsuhiro Nojima
  • Patent number: 8303780
    Abstract: The present invention relates to a method for forming a dry etching mask. A plurality of aluminum oxide films are sequentially sputtered on a material to be dry etched in such a manner that etching rate with respect to reactive ion etching increases toward a lower layer. On a laminated film of the plurality of aluminum oxide films, there is formed a first mask that has etching resistance with respect to the reactive ion etching. Reactive ion etching is performed from above the first mask to form a second mask of the laminated film.
    Type: Grant
    Filed: September 30, 2008
    Date of Patent: November 6, 2012
    Assignee: TDK Corporation
    Inventors: Kento Edakara, Hiromichi Umehara, Noriaki Kasahara, Michitaka Nishiyama
  • Publication number: 20120026629
    Abstract: The present invention relates to a magnetic head, a manufacturing method therefor, a head assembly, and a magnetic recording/reproducing apparatus. According to the present invention, it includes a magnetic pole layer, a non-magnetic layer, a trailing gap layer, and a trailing shield layer. The magnetic pole layer has a pole tip exposed on a magnetic medium-facing surface. The non-magnetic layer is laid on the magnetic pole layer. The trailing shield layer is exposed on the magnetic medium-facing surface and laid over the magnetic pole layer and the non-magnetic layer with the trailing gap layer between. The magnetic pole layer and the non-magnetic layer have a continuous tapered face opposed to a lower side of the trailing shield layer. Moreover, the tapered face extends from a trailing edge of the pole tip at a constant inclination angle.
    Type: Application
    Filed: July 28, 2010
    Publication date: February 2, 2012
    Applicant: TDK CORPORATION
    Inventors: Kei HIRATA, Kenkichi Anagawa, Michitaka Nishiyama, Hideyuki Yatsu, Shin Narushima, Hisayoshi Watanabe, Tatsuhiro Nojima
  • Patent number: 8102622
    Abstract: In a perpendicular magnetic write head manufacturing method a magnetic layer is formed on a substrate. On the magnetic layer, first and second nonmagnetic layers are formed with different materials. A mask pattern is formed on the second nonmagnetic layer, and the second nonmagnetic layer in a region not covered with the mask pattern is removed. Thereby, the patterned second nonmagnetic layer is formed while leaving the first nonmagnetic layer. The mask pattern is removed and a milling process is selectively performed on the first nonmagnetic layer and the magnetic layer with the patterned second nonmagnetic layer as a mask to remove all of the first nonmagnetic layer in an exposed region and to dig down the magnetic layer in the exposed region, thereby forming a main magnetic pole layer having an inclined part whose thickness decreases with distance from an edge position of the patterned second nonmagnetic layer.
    Type: Grant
    Filed: January 5, 2009
    Date of Patent: January 24, 2012
    Assignee: TDK Corporation
    Inventors: Atsushi Yamaguchi, Michitaka Nishiyama, Shin Narushima, Hiromichi Umehara, Makoto Sato, Tatsuhiro Nojima
  • Patent number: 8080167
    Abstract: The present invention relates to a shaping method of a thin film layer and a manufacturing method of a perpendicular recording magnetic head using the same. In the thin film layer shaping method according to the present invention, since a second thin film of a lower etching rate is etched by a preliminary etching amount allowing for a difference between the etching rate of the second thin film and an etching rate of a first thin film in side-by-side relationship with each other, both the first and second thin films can be etched by the same etching amount through a subsequent etching step, so that the thin film layer can be shaped into a given shape. Thus, the surface of the thin film layer can be planarized.
    Type: Grant
    Filed: February 20, 2009
    Date of Patent: December 20, 2011
    Assignee: TDK Corporation
    Inventors: Hisayoshi Watanabe, Toshiomi Yokoyama, Nobuyuki Mori, Akihiro Kaneko, Michitaka Nishiyama, Kenji Yokoyama
  • Publication number: 20100302680
    Abstract: A perpendicular magnetic write head includes: a magnetic pole having an end face on an air bearing surface; and side shield layers each having an end face on the air bearing surface, and arranged on both sides, in a write track width direction, of the magnetic pole with a side gap in between. The end face of the magnetic pole has a geometry in which a width at a trailing edge is larger than a width at a leading edge. Relationship D1<D2, D1<D3, and D3?D2 are satisfied in the air bearing surface, where D1 is a gap length of the side gap at the trailing edge, D2 is a gap length of the side gap at the leading edge, and D3 is a gap length of the side gap at any position between the trailing edge and the leading edge.
    Type: Application
    Filed: June 1, 2009
    Publication date: December 2, 2010
    Applicant: TDK CORPORATION
    Inventors: Kei Hirata, Takeo Kagami, Tatsuhiro Nojima, Hisayoshi Watanabe, Michitaka Nishiyama
  • Publication number: 20100213163
    Abstract: The present invention relates to a shaping method of a thin film layer and a manufacturing method of a perpendicular recording magnetic head using the same. In the thin film layer shaping method according to the present invention, since a second thin film of a lower etching rate is etched by a preliminary etching amount allowing for a difference between the etching rate of the second thin film and an etching rate of a first thin film in side-by-side relationship with each other, both the first and second thin films can be etched by the same etching amount through a subsequent etching step, so that the thin film layer can be shaped into a given shape. Thus, the surface of the thin film layer can be planarized.
    Type: Application
    Filed: February 20, 2009
    Publication date: August 26, 2010
    Applicant: TDK CORPORATION
    Inventors: Hisayoshi Watanabe, Toshiomi Yokoyama, Nobuyuki Mori, Akihiro Kaneko, Michitaka Nishiyama, Kenji Yokoyama
  • Publication number: 20100172054
    Abstract: In a perpendicular magnetic write head manufacturing method a magnetic layer is formed on a substrate. On the magnetic layer, first and second nonmagnetic layers are formed with different materials. A mask pattern is formed on the second nonmagnetic layer, and the second nonmagnetic layer in a region not covered with the mask pattern is removed Thereby, the patterned second nonmagnetic layer is formed while leaving the first nonmagnetic layer. The mask pattern is removed and a milling process is selectively performed on the first nonmagnetic layer and the magnetic layer with the patterned second nonmagnetic layer as a mask to remove all of the first nonmagnetic layer in an exposed region and to dig down the magnetic layer in the exposed region, thereby forming a main magnetic pole layer having an inclined part whose thickness decreases with distance from an edge position of the patterned second nonmagnetic layer.
    Type: Application
    Filed: January 5, 2009
    Publication date: July 8, 2010
    Applicant: TDK CORPORATION
    Inventors: Atsushi Yamaguchi, Michitaka Nishiyama, Shin Narushima, Hiromichi Umehara, Makoto Sato, Tatsuhiro Nojima