Patents by Inventor Hoa V. Do

Hoa V. Do 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: 9552837
    Abstract: In one general embodiment, a magnetic medium includes a recording layer having at least three exchange control layers each having a magnetic moment less than 100 emu/cc, and four magnetic layers separated from one another by the exchange control layers. An uppermost of the magnetic layers is doped with oxygen. In another general embodiment, a magnetic medium includes a recording layer having at least three exchange control layers and four magnetic layers separated from one another by the exchange control layers. An uppermost of the magnetic layers has an oxygen content of greater than 0.5 vol %. An average pitch of magnetic grains in a lowermost of the magnetic layers is 9 nm or less. A lowermost of the magnetic layers has an oxide content of at least 20 vol %.
    Type: Grant
    Filed: November 1, 2013
    Date of Patent: January 24, 2017
    Assignee: HGST Netherlands B.V.
    Inventors: Hoa V. Do, Sylvia H. Florez, Yoshihiro Ikeda, Kentaro Takano, Bruce D. Terris, Qing Zhu
  • Publication number: 20150124350
    Abstract: In one general embodiment, a magnetic medium includes a recording layer having at least three exchange control layers each having a magnetic moment less than 100 emu/cc, and four magnetic layers separated from one another by the exchange control layers. An uppermost of the magnetic layers is doped with oxygen. In another general embodiment, a magnetic medium includes a recording layer having at least three exchange control layers and four magnetic layers separated from one another by the exchange control layers. An uppermost of the magnetic layers has an oxygen content of greater than 0.5 vol %. An average pitch of magnetic grains in a lowermost of the magnetic layers is 9 nm or less. A lowermost of the magnetic layers has an oxide content of at least 20 vol %.
    Type: Application
    Filed: November 1, 2013
    Publication date: May 7, 2015
    Applicant: HGST Netherlands B.V.
    Inventors: Hoa V. Do, Sylvia H. Florez, Yoshihiro Ikeda, Kentaro Takano, Bruce D. Terris, Qing Zhu
  • Patent number: 8747628
    Abstract: A method according to one embodiment includes forming a high Ku first oxide magnetic layer above a substrate by sputtering; forming a low Ku second oxide magnetic layer above the first oxide magnetic layer by sputtering; forming an exchange coupling layer of CoCrPt-oxide above the second oxide magnetic layer; and forming a magnetic cap layer above the exchange coupling layer. Additional systems and methods are also presented.
    Type: Grant
    Filed: April 3, 2012
    Date of Patent: June 10, 2014
    Assignee: HGST Netherlands B.V.
    Inventors: Xiaoping Bian, Jack Jyh-Kau Chang, Qing Dai, Hoa V. Do, Yoshihiro Ikeda, Kentaro Takano, Chu S. Tran
  • Publication number: 20120186974
    Abstract: A method according to one embodiment includes forming a high Ku first oxide magnetic layer above a substrate by sputtering; forming a low Ku second oxide magnetic layer above the first oxide magnetic layer by sputtering; forming an exchange coupling layer of CoCrPt-oxide above the second oxide magnetic layer; and forming a magnetic cap layer above the exchange coupling layer. Additional systems and methods are also presented.
    Type: Application
    Filed: April 3, 2012
    Publication date: July 26, 2012
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Xiaoping Bian, Jack Jyh-Kau Chang, Qing Dai, Hoa V. Do, Yoshihiro Ikeda, Kentaro Takano, Chu S. Tran
  • Patent number: 8168310
    Abstract: A magnetic storage medium according to one embodiment includes a substrate; a first oxide magnetic layer formed above the substrate; a second oxide magnetic layer formed above the first oxide magnetic layer; an exchange coupling layer formed above the second oxide magnetic layer, the exchange coupling layer comprising an oxide; and a magnetic cap layer formed above the exchange coupling layer. A method according to one embodiment includes forming a high Ku first oxide magnetic layer above a substrate by sputtering; forming a low Ku second oxide magnetic layer above the first oxide magnetic layer by sputtering; forming an exchange coupling layer of CoCrPt-oxide above the second oxide magnetic layer; and forming a magnetic cap layer above the exchange coupling layer. Additional systems and methods are also presented.
    Type: Grant
    Filed: December 15, 2009
    Date of Patent: May 1, 2012
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Xiaoping Bian, Jack Jyh-Kau Chang, Qing Dai, Hoa V. Do, Yoshihiro Ikeda, Kentaro Takano, Chu S. Tran
  • Publication number: 20110141621
    Abstract: A magnetic storage medium according to one embodiment includes a substrate; a first oxide magnetic layer formed above the substrate; a second oxide magnetic layer formed above the first oxide magnetic layer; an exchange coupling layer formed above the second oxide magnetic layer, the exchange coupling layer comprising an oxide; and a magnetic cap layer formed above the exchange coupling layer. A method according to one embodiment includes forming a high Ku first oxide magnetic layer above a substrate by sputtering; forming a low Ku second oxide magnetic layer above the first oxide magnetic layer by sputtering; forming an exchange coupling layer of CoCrPt-oxide above the second oxide magnetic layer; and forming a magnetic cap layer above the exchange coupling layer. Additional systems and methods are also presented.
    Type: Application
    Filed: December 15, 2009
    Publication date: June 16, 2011
    Inventors: Xiaoping Bian, Jack Jyh-Kau Chang, Qing Dai, Hoa V. Do, Yoshihiro Ikeda, Kentaro Takano, Chu S. Tran
  • Patent number: 7879470
    Abstract: A method for improving magnetic grain segregation in perpendicular recording media includes providing a substrate comprising a rigid support structure, depositing a soft underlayer on top of the substrate depositing an intermediate layer on top of the soft underlayer, providing a plurality of prospective segregants, determining the surface energies and the heat of formation of the prospective segregants and selecting the prospective segregant with a low surface energy and a high heat of formation. The method also includes providing at least one layer with surface energies progressively increasing to minimize the difference between the surface energy of a carbon overcoat and the segregant.
    Type: Grant
    Filed: November 15, 2007
    Date of Patent: February 1, 2011
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Qing Dai, Hoa V. Do, Bruno Marchon, Kentaro Takano
  • Publication number: 20090130490
    Abstract: A method for improving magnetic grain segregation in perpendicular recording media includes providing a substrate comprising a rigid support structure, depositing a soft underlayer on top of the substrate depositing an intermediate layer on top of the soft underlayer, providing a plurality of prospective segregants, determining the surface energies and the heat of formation of the prospective segregants and selecting the prospective segregant with a low surface energy and a high heat of formation. The method also includes providing at least one layer with surface energies progressively increasing to minimize the difference between the surface energy of a carbon overcoat and the segregant.
    Type: Application
    Filed: November 15, 2007
    Publication date: May 21, 2009
    Inventors: Qing Dai, Hoa V. Do, Bruno Marchon, Kentaro Takano