Patents by Inventor Geon Choe

Geon Choe 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: 7038891
    Abstract: A method and apparatus for providing precise control of magnetic coupling field in NiMn top spin valve heads and amplitude enhancement is disclosed. The magnetic coupling between free and pinned layers in NiMn top spin valve heads is precisely controlled by employing the surface oxidation of Cu seed layer or/and Cu spacer layer that improve both the interfacial quality and the crystalline texture. According to the present invention the magnitude of coupling field can be precisely controlled without affecting resistance, and the amplitude of giant magneto-resistive(GMR) heads is improved by 15% at the same coupling field without affecting asymmetry performance. Thus, the present invention improves not only the interfacial roughness, but also improves the magnetic layer texture. The oxidation of Cu seed layer in the NiMn top spin valve structure provides more robust process with good control in coupling field that affects asymmetry of a GMR head.
    Type: Grant
    Filed: January 2, 2002
    Date of Patent: May 2, 2006
    Assignee: International Business Machines Corporation
    Inventor: Geon Choe
  • Patent number: 6980405
    Abstract: A method and apparatus for providing precise control of magnetic coupling field in NiMn top spin valve heads and amplitude enhancement is disclosed. The magnetic coupling between free and pinned layers in NiMn top spin valve heads is precisely controlled by employing the surface oxidation of Cu seed layer or/and Cu spacer layer that improve both the interfacial quality and the crystalline texture. According to the present invention the magnitude of coupling field can be precisely controlled without affecting resistance, and the amplitude of giant magneto-resistive(GMR) heads is improved by 15% at the same coupling field without affecting asymmetry performance. Thus, the present invention improves not only the interfacial roughness, but also improves the magnetic layer texture. The oxidation of Cu seed layer in the NiMn top spin valve structure provides more robust process with good control in coupling field that affects asymmetry of a GMR head.
    Type: Grant
    Filed: June 30, 2003
    Date of Patent: December 27, 2005
    Assignee: International Business Machines Corporation
    Inventor: Geon Choe
  • Patent number: 6811890
    Abstract: The present invention is directed to a disk for information storage. The disk, in one embodiment, comprises a substrate 204, antiferromagnetically exchange coupled first and second ferromagnetic films 220 and 236, a spacer film 228, and at least one buffer film 232 located between the first and second ferromagnetic films. One or more of the following statements is true with respect to the buffer film 232: (i) the buffer film 232 is paramagnetic; (ii) the buffer film 232 is superparamagnetic at temperatures of about 50° C. or less; and (iii) a lattice mismatch between the buffer film 232 and at least one of the first and second ferromagnetic films 220 and 236 in contact with the buffer film is about 5% or less.
    Type: Grant
    Filed: August 23, 2002
    Date of Patent: November 2, 2004
    Assignee: Maxtor Corporation
    Inventors: Jianing Richard Zhou, Geon Choe, Kenneth E. Johnson
  • Publication number: 20040004791
    Abstract: A method and apparatus for providing precise control of magnetic coupling field in NiMn top spin valve heads and amplitude enhancement is disclosed. The magnetic coupling between free and pinned layers in NiMn top spin valve heads is precisely controlled by employing the surface oxidation of Cu seed layer or/and Cu spacer layer that improve both the interfacial quality and the crystalline texture. According to the present invention the magnitude of coupling field can be precisely controlled without affecting resistance, and the amplitude of giant magneto-resistive(GMR) heads is improved by 15% at the same coupling field without affecting asymmetry performance. Thus, the present invention improves not only the interfacial roughness, but also improves the magnetic layer texture. The oxidation of Cu seed layer in the NiMn top spin valve structure provides more robust process with good control in coupling field that affects asymmetry of a GMR head.
    Type: Application
    Filed: June 30, 2003
    Publication date: January 8, 2004
    Applicant: International Business Machines Corporation
    Inventor: Geon Choe
  • Publication number: 20030123201
    Abstract: A method and apparatus for providing precise control of magnetic coupling field in NiMn top spin valve heads and amplitude enhancement is disclosed. The magnetic coupling between free and pinned layers in NiMn top spin valve heads is precisely controlled by employing the surface oxidation of Cu seed layer or/and Cu spacer layer that improve both the interfacial quality and the crystalline texture. According to the present invention the magnitude of coupling field can be precisely controlled without affecting resistance, and the amplitude of giant magneto-resistive(GMR) heads is improved by 15% at the same coupling field without affecting asymmetry performance. Thus, the present invention improves not only the interfacial roughness, but also improves the magnetic layer texture. The oxidation of Cu seed layer in the NiMn top spin valve structure provides more robust process with good control in coupling field that affects asymmetry of a GMR head.
    Type: Application
    Filed: January 2, 2002
    Publication date: July 3, 2003
    Applicant: International Business Machines Corporation
    Inventor: Geon Choe
  • Publication number: 20030091798
    Abstract: A perpendicular magnetic recording medium having good perpendicular magnetic anisotropy. The magnetic recording medium includes a tantalum (Ta) seedlayer and a ruthenium (Ru) underlayer. The magnetic recording layer can be fabricated from cobalt (Co) alloys. With the Ta seedlayer, the perpendicular anisotropy and c-axis orientation of the magnetic recording layer are greatly enhanced. Unity squareness is achievable as is a negative nucleation field. The magnetic recording medium can be formed by sputtering the various layers onto a substrate. Thus, a perpendicular magnetic recording medium suitable for mass production is provided.
    Type: Application
    Filed: July 29, 2002
    Publication date: May 15, 2003
    Inventors: Min Zheng, Geon Choe
  • Patent number: 6558774
    Abstract: A magnetic tape comprises a substrate having on one side thereof a magnetic layer serving as a recording surface, and on the other side thereof at least two layers containing inorganic particles which serve as a non-recording surface, wherein said magnetic tape has a region on the side of the non-recording surface along the longitudinal direction of the tape in which a regular pattern for servo tracking having different optical properties from the other major region of the side of the non-recording surface is or can be formed. The layers on the non-recording surface are characterized in that the inorganic particles in the outermost layer are larger than the inorganic particles in the underlying layer(s).
    Type: Grant
    Filed: August 17, 1999
    Date of Patent: May 6, 2003
    Assignee: Quantum Corporation
    Inventors: George A. Saliba, Satya Mallick, Daravuth Seng, Geon Choe
  • Publication number: 20030059649
    Abstract: A magnetic tape comprises a substrate having on one side thereof a magnetic layer serving as a recording surface, and on the other side thereof at least two layers containing inorganic particles which serve as a non-recording surface, wherein said magnetic tape has a region on the side of the non-recording surface along the longitudinal direction of the tape in which a regular pattern for servo tracking having different optical properties from the other major region of the side of the non-recording surface is or can be formed. The layers on the non-recording surface are characterized in that the inorganic particles in the outermost layer are larger than the inorganic particles in the underlying layer(s).
    Type: Application
    Filed: August 16, 2002
    Publication date: March 27, 2003
    Applicant: Quantum Corporation, a California corporation
    Inventors: George A. Saliba, Satya Mallick, Daravuth Seng, Geon Choe