Patents by Inventor Jyh-Kau Chang

Jyh-Kau Chang 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).

  • Publication number: 20160314811
    Abstract: A magnetic storage medium according to one embodiment includes a substrate; an onset layer formed above the substrate, the onset layer comprising ruthenium and titanium oxide; and a magnetic oxide layer formed directly on the onset layer. The onset layer is formed directly on a ruthenium underlayer stack having at least one layer of ruthenium formed under a relatively higher pressure and at least one layer of ruthenium formed under a relatively low pressure. A method according to one embodiment includes sputtering using a target of ruthenium and titanium oxide for forming an onset layer above a substrate, the onset layer comprising ruthenium and titanium oxide; and forming a magnetic oxide layer directly on the onset layer. Additional systems and methods are also presented.
    Type: Application
    Filed: June 30, 2016
    Publication date: October 27, 2016
    Inventors: Xiaoping Bian, Jack Jyh-Kau Chang, Mark F. Mercado, Mohammad T. Mirzamaani, Kai Tang
  • Patent number: 9412404
    Abstract: A magnetic storage medium according to one embodiment includes a substrate; an onset layer formed above the substrate, the onset layer comprising ruthenium and titanium oxide; and a magnetic oxide layer formed directly on the onset layer. A method according to one embodiment includes sputtering using a target of ruthenium and titanium oxide for forming an onset layer above a substrate, the onset layer comprising ruthenium and titanium oxide; and forming a magnetic oxide layer directly on the onset layer. Additional systems and methods are also presented.
    Type: Grant
    Filed: December 15, 2009
    Date of Patent: August 9, 2016
    Assignee: HGST Netherlands B.V.
    Inventors: Xiaoping Bian, Jack Jyh-Kau Chang, Mark F. Mercado, Mohammad T. Mirzamaani, Kai Tang
  • Patent number: 9245564
    Abstract: According to one embodiment, a soft underlayer structure includes a coupling layer, at least one outer soft underlayer positioned above and below the coupling layer, and at least one inner soft underlayer positioned above and below the coupling layer between the coupling layer and the associated outer soft underlayer, where the inner soft underlayers have a saturation magnetic flux density and/or a thickness that is different than a saturation magnetic flux density and/or a thickness of the outer soft underlayers.
    Type: Grant
    Filed: April 29, 2014
    Date of Patent: January 26, 2016
    Assignee: HGST Netherlands B.V.
    Inventors: Thomas C. Arnoldussen, Jack Jyh-Kau Chang, Arien M. Ghaderi, Zhupei Shi
  • Publication number: 20150310884
    Abstract: According to one embodiment, a soft underlayer structure includes a coupling layer, at least one outer soft underlayer positioned above and below the coupling layer, and at least one inner soft underlayer positioned above and below the coupling layer between the coupling layer and the associated outer soft underlayer, where the inner soft underlayers have a saturation magnetic flux density and/or a thickness that is different than a saturation magnetic flux density and/or a thickness of the outer soft underlayers.
    Type: Application
    Filed: April 29, 2014
    Publication date: October 29, 2015
    Applicant: HGST Netherlands B.V.
    Inventors: Thomas C. Arnoldussen, Jack Jyh-Kau Chang, Arien M. Ghaderi, Zhupei Shi
  • Patent number: 9082442
    Abstract: Perpendicular magnetic recording media has been enhanced by controlling the initial growth of magnetic oxide layers and increased magnetic isolation between the grains in the initial magnetic layer. An onset magnetic oxide layer is sputter deposited in an argon-oxygen gas mixture between the main CoPtCr-oxide magnetic layers and the underlying Ru layer. The insertion of the onset magnetic oxide layer enhances the coercivity of the oxide magnetic layers and also improves the nucleation field. The media signal-to-noise ratio and bit error rate also are significantly improved due to the improvement of the initial segregation of Co magnetic grains in the magnetic oxide layers.
    Type: Grant
    Filed: September 15, 2008
    Date of Patent: July 14, 2015
    Assignee: HGST NETHERLANDS B.V.
    Inventors: Xiaoping Bian, Jyh-Kau Chang, Weikang Shen, Zhupei Shi, Kai Tang
  • 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
  • Patent number: 8580409
    Abstract: Perpendicular magnetic recording (PMR) media and methods of fabricating PMR media are described. The PMR media includes, among other layers, an underlayer, a first onset layer on the underlayer, a second onset layer on the first onset layer, and a perpendicular magnetic recording layer on the second onset layer. The second onset layer has a magnetic moment which is higher than both a magnetic moment of the first onset layer and a magnetic moment of the perpendicular magnetic recording layer.
    Type: Grant
    Filed: November 9, 2009
    Date of Patent: November 12, 2013
    Assignee: HGST Netherlands B.V.
    Inventors: Xiaoping Bian, Jack Jyh-Kau Chang, Zhupei Shi
  • 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: 20110141609
    Abstract: A magnetic storage medium according to one embodiment includes a substrate; an onset layer formed above the substrate, the onset layer comprising ruthenium and titanium oxide; and a magnetic oxide layer formed directly on the onset layer. A method according to one embodiment includes sputtering using a target of ruthenium and titanium oxide for forming an onset layer above a substrate, the onset layer comprising ruthenium and titanium oxide; and forming a magnetic oxide layer directly on the onset 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, Mark F. Mercado, Mohammad T. Mirzamaani, Kai Tang
  • 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
  • Publication number: 20110111261
    Abstract: Perpendicular magnetic recording (PMR) media and methods of fabricating PMR media are described. The PMR media includes, among other layers, an underlayer, a first onset layer on the underlayer, a second onset layer on the first onset layer, and a perpendicular magnetic recording layer on the second onset layer. The second onset layer has a magnetic moment which is higher than both a magnetic moment of the first onset layer and a magnetic moment of the perpendicular magnetic recording layer.
    Type: Application
    Filed: November 9, 2009
    Publication date: May 12, 2011
    Inventors: Xiaoping Bian, Jack Jyh-Kau Chang, Zhupei Shi
  • Publication number: 20100067149
    Abstract: Perpendicular magnetic recording media has been enhanced by controlling the initial growth of magnetic oxide layers and increased magnetic isolation between the grains in the initial magnetic layer. An onset magnetic oxide layer is sputter deposited in an argon-oxygen gas mixture between the main CoPtCr-oxide magnetic layers and the underlying Ru layer. The insertion of the onset magnetic oxide layer enhances the coercivity of the oxide magnetic layers and also improves the nucleation field. The media signal-to-noise ratio and bit error rate also are significantly improved due to the improvement of the initial segregation of Co magnetic grains in the magnetic oxide layers.
    Type: Application
    Filed: September 15, 2008
    Publication date: March 18, 2010
    Applicant: HITACHI GLOBAL STORAGE TECHNOLOGIES NETHERLANDS BV
    Inventors: Xiaoping Bian, Jyh-Kau Chang, Weikang Shen, Zhupei Shi, Kai Tang
  • Publication number: 20020132139
    Abstract: A magnetic recording medium having a dual magnetic structure layer for the separate control of KuV/kT and SNR to achieve high SNR, increased overwrite (OW) capability and good thermal stability. The magnetic recording medium includes a nonmagnetic Al—Mg substrate followed by the addition of a NiP layer electrolessly plated on the surface of the substrate. A dual-film magnetic layer is formed on the substrate. The dual-film magnetic structure comprises an upper first magnetic film of CoCrPtB alloy and a lower second magnetic film of a CoCrPtTaB alloy. The composition and thickness of each magnetic film in the dual-film magnetic structure allows for the simultaneous ability of the magnetic recording medium to obtain high SNR, increased OW capability and good thermal stability to improve the overall performance of the media.
    Type: Application
    Filed: January 5, 2001
    Publication date: September 19, 2002
    Inventors: Jack Jyh-Kau Chang, Yi-Hong Huang, Wu-Sun Wang, Chun-Lee Liang, I-An Chen, Lu-Mei Liang
  • Patent number: 6010795
    Abstract: A magnetic recording medium is formed by depositing a Cr-containing sub-underlayer on a surface oxidized seed layer, such as NiP, with direct current (DC) magnetron sputtering, depositing a NiAl or FeAl underlayer on the sub-underlayer, and depositing a Cr-containing intermediate layer on the NiAl or FeAl underlayer. The medium features high coercivity, low noise, and (200)-dominant underlayer crystallographic orientation, even with sub-underlayer deposition at temperatures as low as about 25.degree. C. The medium is suitable for high density longitudinal magnetic recording.
    Type: Grant
    Filed: October 17, 1997
    Date of Patent: January 4, 2000
    Assignee: Seagate Technology, Inc.
    Inventors: Qixu Chen, Jyh-Kau Chang, Charles Leu, Ga-Lane Chen
  • Patent number: 5879783
    Abstract: A magnetic recording medium exhibiting low medium noise is formed by depositing a seed layer on a glass or a glass-ceramic substrate and oxidizing the deposited seed layer, under controlled conditions to induce controlled surface microroughness. The subsequently sputter deposited underlayer exhibits a fine average grain size, such as less than about 20 nm. The magnetic alloy sputter deposited and epitaxially grown on the underlayer exhibits a fine average grain size, such as less than about 15 nm, and magnetic clusters reduced in size.
    Type: Grant
    Filed: January 2, 1997
    Date of Patent: March 9, 1999
    Assignee: Seagate Technology, Inc.
    Inventors: Jyh-Kau Chang, Qixu Chen, Ga-Lane Chen