Patents by Inventor Yugang Wang

Yugang Wang 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: 7337530
    Abstract: A method of making a perpendicular magnetic recording head for use in a data storage device includes forming a first pole layer, a second pole layer, a third pole layer, and a shield layer of a write section. The first pole layer, second pole layer, third pole layer, and shield layer are formed without using a chemical mechanical polishing process. The method next includes concurrently trimming the shield layer and a write pole that is defined by the third pole layer to a predetermined track width. In the trimming step, the shield layer is used as a mask for the write pole.
    Type: Grant
    Filed: January 30, 2007
    Date of Patent: March 4, 2008
    Assignee: Western Digital (Fremont), LLC
    Inventors: Kroum S. Stoev, Francis H. Liu, Yugang Wang
  • Patent number: 7310204
    Abstract: A magnetic head for writing information on a relatively-moving medium has a pair of substantially flat soft magnetic pole layers separated by a pair of coil layers. A soft magnetic pedestal adjoins the leading pole layer adjacent to a medium-facing surface and is spaced from the second pole layer by a nanoscale nonferromagnetic gap, the pedestal having a layer of high magnetic saturation material that defines a throat height and extends beyond the throat height. A second high magnetic saturation material adjoins the trailing pole layer and either terminates at the throat height to form a second pedestal or extends to reach a magnetic backgap structure that magnetically couples the pole layers. The MR sensor can be located closer than the write transducer to the trailing end of the head to reduce separation between the read transducer and the write transducer.
    Type: Grant
    Filed: December 19, 2003
    Date of Patent: December 18, 2007
    Assignee: Western Digital (Fremont), LLC
    Inventors: Kroum S. Stoev, Francis H. Liu, Yugang Wang, Yingjian Chen
  • Patent number: 7248433
    Abstract: A magnetic head is disclosed that has first and second substantially flat soft magnetic pole layers that are magnetically coupled together in a backgap region that is removed from the medium-facing surface; a soft magnetic pedestal having a leading edge and a trailing edge, the trailing edge adjoining the second pole layer adjacent to the medium-facing surface, the leading edge defining a throat area that is spaced from the first pole layer by a submicron nonferromagnetic gap and defining an apex area that is spaced from the first pole layer by a greater separation than the gap, the throat area meeting the apex area at a throat height; and a plurality of substantially parallel, electrically conductive sections disposed between the first and second pole layers, the conductive sections disposed in a single layer that is aligned along a plane that intersects the pedestal and the backgap region.
    Type: Grant
    Filed: February 2, 2004
    Date of Patent: July 24, 2007
    Assignee: Western Digital (Fremont), Inc.
    Inventors: Kroum S Stoev, Francis H Liu, Yugang Wang
  • Patent number: 7193815
    Abstract: A read/write head for use in a perpendicular magnetic recording head in a data storage system. The read/write head includes a write section that is comprised of a first pole layer, a second pole layer, a third pole layer, and a shield layer. The third pole layer defines a write pole tip, and the third pole layer and the shield layer are separated from each other to define a write gap therebetween. At least part of the shield layer has a generally uniform width, and wherein the write pole tip defines a track width that is substantially equal to the uniform width of the shield layer. According to one embodiment the entire shield layer has a generally uniform width that is substantially equal to the track width. According to another embodiment, the shield layer includes a lower section and an upper section, wherein the lower section has a generally uniform width along its entire length, and wherein the upper section is wider than the lower section.
    Type: Grant
    Filed: April 6, 2004
    Date of Patent: March 20, 2007
    Assignee: Western Digital (Fremont), Inc.
    Inventors: Kroum S. Stoev, Francis H. Liu, Yugang Wang
  • Patent number: 7126788
    Abstract: A magnetic head for writing information on perpendicular media has a write pole tip, a return pole tip and a deflection pole tip is disclosed. The return pole tip has a media-facing area at least two orders of magnitude greater than that of the write pole tip, and the deflection pole tip is spaced from a trailing corner of the write pole tip by a submicron nonferromagnetic gap. Magnetic flux emanating from the write pole tip is strongest adjacent the trailing corner and directed at an angle that is not perpendicular to the write pole tip. The angled flux provides increased torque to rotate magnetic dipoles in the adjacent media layer that are oriented substantially perpendicular to the disk surface. The media may have a soft magnetic underlayer that is spaced from the write pole tip by a distance similar to the gap spacing.
    Type: Grant
    Filed: November 26, 2003
    Date of Patent: October 24, 2006
    Assignee: Western Digital (Fremont), Inc.
    Inventors: Francis H. Liu, Kroum S. Stoev, Yugang Wang
  • Patent number: 7126790
    Abstract: A magnetic head for writing information on perpendicular media has a write pole tip and a return pole tip with a media-facing area at least two orders of magnitude greater than that of the write pole tip, the return pole tip is spaced from a trailing corner of the write pole tip by a submicron nonferromagnetic gap. Magnetic flux emanating from the write pole tip is strongest adjacent the trailing corner and directed at an angle that is not perpendicular to the write pole tip. The angled flux provides increased torque to rotate magnetic dipoles in the adjacent media layer that are oriented substantially perpendicular to the disk surface. The media may have a soft magnetic underlayer that is spaced from the write pole tip by a distance similar to the gap spacing.
    Type: Grant
    Filed: November 26, 2003
    Date of Patent: October 24, 2006
    Assignee: Western Digital (Fremont), Inc.
    Inventors: Francis H. Liu, Kroum S. Stoev, Yugang Wang
  • Patent number: 7116517
    Abstract: A T-shaped pole tip portion of an upper pole of a write element for a magnetic disk drive is provided. One end of the pole tip portion, constituting the bottom of the “T,” forms a narrow nose segment at an air bearing surface, while a wing segment at the opposite end of the pole tip portion constitutes the cross-bar top of the “T.” A transition segment extends between the nose segment and the wing segment. A yoke portion of the upper pole includes a surface that is parallel to the air bearing surface and recessed therefrom by a P3R depth. The transition segment does not widen significantly until after the P3R depth, accordingly, the wing segment is recessed from the air bearing surface by more than the P3R depth.
    Type: Grant
    Filed: December 18, 2002
    Date of Patent: October 3, 2006
    Assignee: Western Digital (Fremont), Inc.
    Inventors: Qing He, Hirohiko Kamimura, Shuhei Otani, Yugang Wang, David J. Seagle
  • Patent number: 7113366
    Abstract: A thin film electromagnetic head has an inductive transducer with a double-nosed ferromagnetic trailing pole layer. The trailing pole layer has a trailing pole tip disposed adjacent to a media-facing surface, a trailing pole yoke disposed distal to the media-facing surface, and a trailing pole nose disposed between the trailing pole tip and the trailing pole yoke. The media-facing surface extends as a substantially flat surface in all directions from the trailing pole tip. The length of the trailing pole nose may be at least twice as long as the trailing pole tip length. The width of the trailing pole nose can be 10 to 30 times as wide as the trailing pole tip width. An inductive transducer having a double-nosed trailing pole layer provides a higher ratio of on-track to off-track write fields, thereby improving the density with which data can be written to the recording media. Such a double-nosed trailing pole layer can be used in transducers for either longitudinal or perpendicular magnetic recording.
    Type: Grant
    Filed: November 7, 2002
    Date of Patent: September 26, 2006
    Assignee: Western Digital (Fremont), Inc.
    Inventors: Yugang Wang, Kroum Stoev, Francis Liu, Yingjian Chen
  • Patent number: 6912106
    Abstract: A method and system for providing a recording head is disclosed. The method and system include providing a first pole, a second pole, a write gap and at least one coil. The write cap separates the first pole from the second pole. The coil(s) include a plurality of turns and is between the first and second poles. The first pole includes a pedestal that has a first portion and a second portion. The first portion includes a high moment electroplated material. The second portion includes a hot seed layer that has a high moment sputtered material. The second portion of the first pole is adjacent to the write gap.
    Type: Grant
    Filed: August 6, 2002
    Date of Patent: June 28, 2005
    Assignee: Western Digital (Fremont), Inc.
    Inventors: Yingjian Chen, Qing He, Yugang Wang, Kroum Stoev, Francis Liu, Xiaozhong Dang
  • Patent number: 6906894
    Abstract: A read/write head and method of making the same are used in a data storage system, such as a disk drive, for perpendicular magnetic recording of data. The head employs a two-layer pole design with a main pole made of sputtered high moment magnetic material, and an adjunct pole made of electroplated soft magnetic film. The main pole is used to write data onto the medium, and is formed over the write coil. The adjunct pole is substantially recessed from the air bearing surface and is formed over the main pole. The present head design significantly enhances the magnetic write field, and substantially reduces side-writing that result in accidental erasure of data in adjacent tracks on the magnetic recording medium.
    Type: Grant
    Filed: July 29, 2004
    Date of Patent: June 14, 2005
    Assignee: Western Digital (Fremont), Inc.
    Inventors: Yingjian Chen, Xiaozhong Dang, Francis H. Liu, Kroum Stoev, Hai Jiang, Yugang Wang, Xizeng Shi
  • Publication number: 20050007696
    Abstract: A read/write head and method of making the same are used in a data storage system, such as a disk drive, for perpendicular magnetic recording of data. The head employs a two-layer pole design with a main pole made of sputtered high moment magnetic material, and an adjunct pole made of electroplated soft magnetic film. The main pole is used to write data onto the medium, and is formed over the write coil. The adjunct pole is substantially recessed from the air bearing surface and is formed over the main pole. The present head design significantly enhances the magnetic write field, and substantially reduces side-writing that result in accidental erasure of data in adjacent tracks on the magnetic recording medium.
    Type: Application
    Filed: July 29, 2004
    Publication date: January 13, 2005
    Applicant: Western Digital (Fremont), Inc.
    Inventors: Yingjian Chen, Xiaozhong Dang, Francis Liu, Kroum Stoev, Hai Jiang, Yugang Wang, Xizeng Shi
  • Patent number: 6809899
    Abstract: Electromagnetic transducers are disclosed having write poles with a leading edge that is smaller than a trailing edge, which can reduce erroneous writing for perpendicular recording systems. The write poles may have a trapezoidal shape when viewed from a direction of an associated medium. The write poles may be incorporated in heads or sliders that also contain read elements such as magnetoresistive sensors, and may be employed with information storage systems such as disk drives.
    Type: Grant
    Filed: December 31, 2003
    Date of Patent: October 26, 2004
    Assignee: Western Digital (Fremont), Inc.
    Inventors: Yingjian Chen, Yugang Wang, Francis Liu, Xizeng Shi, Kyusik Sin, Hugh Craig Hiner
  • Patent number: 6791793
    Abstract: A read/write head and method of making the same, are used in a data storage system, such as a disk drive, for perpendicular magnetic recording of data. The head employs a two-layer pole design with a main pole made of sputtered high moment magnetic material, and an adjunct pole made of electroplated soft magnetic film. The adjunct pole is substantially recessed from the air bearing surface. The present head design significantly enhances the magnetic write field, and substantially reduces side-writing that result in accidental erasure of data in adjacent tracks on the magnetic recording medium.
    Type: Grant
    Filed: September 14, 2001
    Date of Patent: September 14, 2004
    Assignee: Western Digital (Fremont), Inc.
    Inventors: Yingjian Chen, Xiaozhong Dang, Francis H. Liu, Kroum Stoev, Hai Jiang, Yugang Wang, Xizeng Shi
  • Patent number: 6754049
    Abstract: Perpendicular recording and magnetoresistive sensing transducers are disclosed having additional coil windings carrying current in an opposite direction to windings encircled by a core. The magnetic influence of the recording transducer on the sense transducer is reduced or eliminated. The inductance of the coils used to drive the recording transducer is reduced, facilitating high-frequency operation. Moreover, the magnetic flux induced by the coils and transmitted by the recording pole tip is increased, improving recording capabilities.
    Type: Grant
    Filed: October 16, 2001
    Date of Patent: June 22, 2004
    Assignee: Western Digital (Fremont), Inc.
    Inventors: David J. Seagle, Yugang Wang
  • Patent number: 6724572
    Abstract: In one aspect, an inductive transducer is disclosed having a leading pole layer and a leading pole tip, with the pole layer being further removed than the pole tip from a media-facing surface. In another aspect, an inductive transducer is disclosed having a magnetic pedestal disposed between a leading pole layer and a leading pole tip, with at least one of the pedestal and pole layer being further removed than the pole tip from a media-facing surface. In another aspect, a leading pole layer or pedestal may have a surface that slopes away from the media-facing surface with increasing distance forward from the leading pole tip.
    Type: Grant
    Filed: February 28, 2002
    Date of Patent: April 20, 2004
    Assignee: Western Digital, Inc.
    Inventors: Kroum Stoev, Yugang Wang, Francis Liu, Yingjian Chen, Xiaozhong Dang
  • Patent number: 6721138
    Abstract: An inductive transducer having first and second magnetic pedestals disposed between first and second magnetic pole layers and adjacent to a media-facing surface, the pedestals separated by a submicron, nonmagnetic gap. The first pedestal extends less than the second pedestal from the media-facing surface, defining a short throat height. The second pedestal extends further to provide sufficient area for stitching to the second pole layer. The stitching and the thickness provided by the pedestals allow plural coil layers to be disposed between the pole layers, and the second pedestal, as well as other features, can be defined by high-resolution photolithography. The two coil layers have lower resistance, lower inductance and allow the pole layers to be shorter, improving performance. All or part of either or both of the pedestals may be formed of high magnetic saturation material, further enhancing performance.
    Type: Grant
    Filed: October 24, 2001
    Date of Patent: April 13, 2004
    Assignee: Western Digital (Fremont), Inc.
    Inventors: Yingjian Chen, Xizeng Shi, Hugh Craig Hiner, Zi-Wen Dong, Francis Liu, Matthew R. Gibbons, Joyce Anne Thompson, William D. Jensen, Chester Xiaowen Chien, Yugang Wang
  • Patent number: 6404706
    Abstract: A head gimbal assembly includes a magneto-resistive read element integrated with a thermally assisted write element. The head gimbal assembly includes an optical waveguide positioned between two write poles to transmit a laser beam to a recording medium. The laser beam heats the medium sufficiently and lowers its coercivity in order to facilitate writing. A laser assembly is attached to a suspension for achieving direct coupling of the laser beam to an input end of the optical waveguide. The laser assembly is produced using cost effective wafer processing techniques. The use of silicon for the mounting block allows it to be used as a heat sink, for conducting heat away from the laser diode and into the suspension.
    Type: Grant
    Filed: October 28, 1999
    Date of Patent: June 11, 2002
    Assignee: Read-Rite Corporation
    Inventors: Ross W Stovall, Yugang Wang, Carl J Carlson
  • Patent number: 6377535
    Abstract: An optical focusing device for focusing an incident optical beam onto a focal plane, as a focal spot. The optical focusing device includes an incident central refractive facet upon which an optical beam impinges, and a high-index glass body through which the incident optical beam passes toward a bottom reflective surface. The bottom reflective surface reflects the optical beam through the body, toward a peripheral reflector. The peripheral reflector focuses the optical beam toward a focal plane on which the focal spot is formed. The focal plane is defined within a pedestal that forms part of the optical focusing device, and that extends from the bottom reflective surface. The central facet is conically shaped for refracting the incident optical beam away from the pedestal, onto the bottom reflective surface.
    Type: Grant
    Filed: October 26, 1998
    Date of Patent: April 23, 2002
    Assignee: Read-Rite Corporation
    Inventors: Hong Chen, Chuan He, Carl J. Carlson, Joseph J. Miceli, Jr., Charles C. Cheng, Yugang Wang
  • Patent number: 6229782
    Abstract: An optical focusing device for focusing an incident optical beam onto a focal plane, as a focal spot. The optical focusing device includes an incident central refractive facet upon which an optical beam impinges, and a high-index glass body through which the incident optical beam passes toward a bottom reflective surface. The bottom reflective surface reflects the optical beam through the body, toward a peripheral reflector. The peripheral reflector focuses the optical beam toward a focal plane on which the focal spot is formed. The focal plane is defined within a pedestal that forms part of the optical focusing device, and that extends from the bottom reflective surface. The central facet is conically shaped for refracting the incident optical beam away from the pedestal, onto the bottom reflective surface.
    Type: Grant
    Filed: October 26, 1998
    Date of Patent: May 8, 2001
    Assignee: Read-Rite Corporation
    Inventors: Yugang Wang, Chuan He, Hong Chen, Joseph J. Miceli, Charles C. Cheng, Ross W. Stovall
  • Patent number: 6130863
    Abstract: A slider supports or stores a device such as an electro-magnetic coil assembly, an electronic component, or an optical component, and includes an underside formed of a taper, a flat or patterned air bearing surface, and a recessed region. The recessed region receives the device without significantly affecting the aerodynamic performance of the air bearing surface, and is located at the slider trailing edge. The weight of the device can be compensated by the suspension gram load. In certain applications the device underside is recessed relative to the air bearing surface, while in other application the device underside is flush with the air bearing surface. The device includes an electrical conductor that extends along the recessed region. According to another embodiment, the slider includes a vertical channel located in a front side of the slider that extends along the entire slider depth. The vertical channel accommodates the electrical conductor of the device.
    Type: Grant
    Filed: January 12, 1998
    Date of Patent: October 10, 2000
    Assignee: Read-Rite Corporation
    Inventors: Yugang Wang, Jimmy Jyhming Shen, Howie Trang, Marcus H. Barnes