Patents by Inventor Zhong Stella Wu

Zhong Stella Wu 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: 10311907
    Abstract: Provided herein is an apparatus, including a magnetically soft underlayer (SUL); an interlayer stack overlying the SUL, wherein the interlayer stack comprises a seed layer of an fcc material; and a perpendicular magnetic recording layer overlying the interlayer stack, wherein a thickness of the SUL in combination with a distance of the SUL from the perpendicular recording layer is sufficient to orient a total magnetic field corresponding to a magnetic transducer head at an angle of about 45°.
    Type: Grant
    Filed: March 28, 2014
    Date of Patent: June 4, 2019
    Assignee: Seagate Technology LLC
    Inventors: Thomas P. Nolan, Li Tang, Yong-Chang Feng, Zhong (Stella) Wu, Samuel D. Harkness, Hans J. Richter, Youfeng Zheng
  • Publication number: 20140313615
    Abstract: Provided herein is an apparatus, including a magnetically soft underlayer (SUL); an interlayer stack overlying the SUL, wherein the interlayer stack comprises a seed layer of an fcc material; and a perpendicular magnetic recording layer overlying the interlayer stack, wherein a thickness of the SUL in combination with a distance of the SUL from the perpendicular recording layer is sufficient to orient a total magnetic field corresponding to a magnetic transducer head at an angle of about 45°.
    Type: Application
    Filed: March 28, 2014
    Publication date: October 23, 2014
    Applicant: SEAGATE TECHNOLOGY LLC
    Inventors: Thomas P. Nolan, Li Tang, Yong-Chang Feng, Zhong (Stella) Wu, Samuel D. Harkness, Hans J. Richter, Youfeng Zheng
  • Publication number: 20140178714
    Abstract: A perpendicular magnetic recording medium having a dual-layer magnetic film is disclosed. The bottom layer is completely exchange decoupled, and the top layer contains a certain amount of exchange coupling optimized for recording performance. Preferably, the bottom magnetic layer contains stable oxide material (for example, TiO2) and other non-magnetic elements (for example, Cr). A method of manufacturing the media is also disclosed.
    Type: Application
    Filed: February 27, 2014
    Publication date: June 26, 2014
    Applicant: Seagate Technology LLC
    Inventors: Zhong Stella Wu, Samuel Dacke Harkness, IV, Mariana Rodica Munteanu, Qixu Chen, Connie Chunling Liu
  • Patent number: 8697260
    Abstract: A perpendicular magnetic recording medium having a dual-layer magnetic film is disclosed. The bottom layer is completely exchange decoupled, and the top layer contains a certain amount of exchange coupling optimized for recording performance. Preferably, the bottom magnetic layer contains stable oxide material (for example, TiO2) and other non-magnetic elements (for example, Cr). A method of manufacturing the media is also disclosed.
    Type: Grant
    Filed: July 25, 2008
    Date of Patent: April 15, 2014
    Assignee: Seagate Technology LLC
    Inventors: Zhong Stella Wu, Samuel Dacke Harkness, IV, Mariana R. Munteanu, Qixu Chen, Connie Chunling Liu
  • Patent number: 8043734
    Abstract: The invention relates to granular perpendicular magnetic recording media with a capping layer comprised of a material having high surface mobility and low surface energy. The capping layer surface is oxidized to produce a passivating surface that is impervious to corrosion.
    Type: Grant
    Filed: July 23, 2008
    Date of Patent: October 25, 2011
    Assignee: Seagate Technology LLC
    Inventors: Samuel Dacke Harkness, IV, Zhong Stella Wu
  • Publication number: 20100215846
    Abstract: A granular perpendicular magnetic recording medium comprises a non-magnetic substrate and a granular perpendicular magnetic recording layer overlying the substrate, comprising a first granular perpendicular magnetic layer proximal the substrate and having a first saturation magnetization (Ms)1, and a second granular perpendicular magnetic layer distal the substrate and having a second, different saturation magnetization (Ms)2. Also disclosed is a method of fabricating the granular perpendicular magnetic recording medium.
    Type: Application
    Filed: April 28, 2010
    Publication date: August 26, 2010
    Applicant: Seagate Technology LLC
    Inventors: Zhong (Stella) Wu, Samuel Dacke Harkness, IV, Hans J. Richter, Alexander Yulievich Dobin
  • Patent number: 7736765
    Abstract: A granular perpendicular magnetic recording medium comprises a non-magnetic substrate and a granular perpendicular magnetic recording layer overlying the substrate, comprising a first granular perpendicular magnetic layer proximal the substrate and having a first saturation magnetization (Ms)1, and a second granular perpendicular magnetic layer distal the substrate and having a second, different saturation magnetization (Ms)2. Also disclosed is a method of fabricating the granular perpendicular magnetic recording medium.
    Type: Grant
    Filed: December 28, 2004
    Date of Patent: June 15, 2010
    Assignee: Seagate Technology LLC
    Inventors: Zhong (Stella) Wu, Samuel Dacke Harkness, IV, Hans J. Richter, Alexander Yulievich Dobin
  • Publication number: 20100021772
    Abstract: The invention relates to granular perpendicular magnetic recording media with a capping layer comprised of a material having high surface mobility and low surface energy. The capping layer surface is oxidized to produce a passivating surface that is impervious to corrosion.
    Type: Application
    Filed: July 23, 2008
    Publication date: January 28, 2010
    Applicant: Seagate Technology LLC
    Inventors: Samuel Dacke Harkness, Zhong Stella Wu
  • Publication number: 20100020441
    Abstract: A perpendicular magnetic recording medium having a dual-layer magnetic film is disclosed. The bottom layer is completely exchange decoupled, and the top layer contains a certain amount of exchange coupling optimized for recording performance. Preferably, the bottom magnetic layer contains stable oxide material (for example, TiO2) and other non-magnetic elements (for example, Cr). A method of manufacturing the media is also disclosed.
    Type: Application
    Filed: July 25, 2008
    Publication date: January 28, 2010
    Applicant: Seagate Technology LLC
    Inventors: Zhong Stella Wu, Samuel Dacke Harkness, Mariana R. Munteanu, Qixu Chen, Connie Chunling Liu
  • Publication number: 20090214896
    Abstract: A perpendicular magnetic recording medium having a substrate, an amorphous soft underlayer of thickness 30 nm or greater, and a granular magnetic recording layer for perpendicular recording is disclosed. The granular magnetic recording layer includes a non-magnetic region between magnetic grains, wherein the non-magnetic region includes metal nitride or metal carbide and provides exchange decoupling between the magnetic grains. The perpendicular recording medium of this invention reduces DC noise and increases media signal-to-noise ratio; it reduces surface roughness, which in turn reduces the head-to-media spacing and the head-to-amorphous soft underlayer spacing.
    Type: Application
    Filed: May 11, 2009
    Publication date: August 27, 2009
    Applicant: Seagate Technology LLC
    Inventors: Thomas Patrick Nolan, Zhong (Stella) Wu, Samuel Dacke Harkness, IV
  • Patent number: 7531248
    Abstract: A perpendicular magnetic recording medium having a substrate, an amorphous soft underlayer of thickness 30 nm or greater, and a granular magnetic recording layer for perpendicular recording is disclosed. The granular magnetic recording layer includes a non-magnetic region between magnetic grains, wherein the non-magnetic region includes metal nitride or metal carbide and provides exchange decoupling between the magnetic grains. The perpendicular recording medium of this invention reduces DC noise and increases media signal-to-noise ratio; it reduces surface roughness, which in turn reduces the head-to-media spacing and the head-to-amorphous soft underlayer spacing.
    Type: Grant
    Filed: December 22, 2004
    Date of Patent: May 12, 2009
    Assignee: Seagate Technology LLC
    Inventors: Thomas Patrick Nolan, Zhong Stella Wu, Samuel D. Harkness, IV
  • Patent number: 7429427
    Abstract: Disclosed are granular magnetic recording media with improved grain segregation and corrosion resistance, comprising a non-magnetic substrate and at least one granular magnetic recording layer formed over the surface, comprised of at least one ferromagnetic material including magnetic grains with grain boundaries and a non-magnetic material comprised of a mixture of metal oxides. Also disclosed are methods for fabricating the improved media.
    Type: Grant
    Filed: December 6, 2004
    Date of Patent: September 30, 2008
    Assignee: Seagate Technology LLC
    Inventors: Zhong (Stella) Wu, Samuel Dacke Harkness
  • Publication number: 20070287031
    Abstract: A perpendicular magnetic recording system, comprises: a perpendicular magnetic recording medium including a non-magnetic substrate having a surface and a stacked plurality of thin film layers forming a layer stack overlying the substrate surface and including a magnetically soft underlayer (SUL) beneath at least one perpendicular magnetic recording layer, wherein the SUL has a saturation magnetization (Ms)—thickness (t) product (Mst) less than about 4 memu/cm2, and a ring-type magnetic transducer head is positioned in spaced adjacency to an upper surface of the layer stack.
    Type: Application
    Filed: June 8, 2006
    Publication date: December 13, 2007
    Inventors: Thomas P. Nolan, Li Tang, Yong-Chang Feng, Zhong (Stella) Wu, Samuel D. Harkness, Hans J. Richter, Youfeng Zheng
  • Patent number: 7282277
    Abstract: A magnetic recording medium including at least one Cu-containing magnetic recording layer (CuML) comprised of a Cu-containing magnetic alloy material selected from the group consisting of: (a) a CoCrPtBCu alloy having a composition represented by the formula Co100-x-y-z-?CrxPtyBzCu?, wherein 0<x?20, 0<y?30, 0<z?24, and 0<??10; (b) a CoCrPtBCu alloy having a composition represented by the formula Co100-x-y-z-?CrxPtyBzCu?, wherein 0<x?30, 0<y?30, 7<z?24, and 0<??10; and (c) a CoCrTaCu alloy having a composition represented by the formula Co100-x-y-?CrxTayCu?, containing less than 30 at. % Cr, up to 8 at. % Ta, and up to 10 at. % Cu.
    Type: Grant
    Filed: April 20, 2004
    Date of Patent: October 16, 2007
    Assignee: Seagate Technology LLC
    Inventors: Mariana Rodica Munteanu, Erol Girt, Samuel Dacke Harkness, IV, Li-Lien Lee, Zhong (Stella) Wu
  • Publication number: 20070237986
    Abstract: A perpendicular magnetic recording medium comprises a non-magnetic substrate having a planar surface and a stack of thin film layers overlying the substrate surface and including at least one perpendicular magnetic recording layer with a magnetic easy axis perpendicular to the plane of the layer stack, wherein a magnetically soft underlayer (“SUL”) is not present in the layer stack. The layer stack includes a first, amorphous and smooth-surfaced underlayer proximal the substrate surface, a second underlayer having a first crystallographic orientation overlying the first underlayer, a third underlayer having a second crystallographic orientation overlying the second underlayer, and at least one perpendicular magnetic recording layer having a crystallographic orientation similar to the second crystallographic orientation overlying the third underlayer.
    Type: Application
    Filed: April 7, 2006
    Publication date: October 11, 2007
    Inventors: Zhong (Stella) Wu, Samuel Harkness, Erol Girt, Qixu Chen, Thomas Nolan
  • Patent number: 7175925
    Abstract: A perpendicular magnetic recording medium, comprising: (a) a non-magnetic substrate having a surface; and (b) a layer stack formed over the substrate surface, comprising in overlying sequence from the substrate surface: (i) a magnetically soft underlayer; (ii) an interlayer structure for crystallographically orienting a layer of a perpendicular magnetic recording material formed thereon; and (iii) at least one crystallographically oriented magnetically hard perpendicular recording layer; wherein the magnetically soft underlayer is sputter-deposited at a sufficiently large target-to-substrate spacing and at a sufficiently low gas pressure selected to provide the underlayer with a smooth surface having a low average surface roughness Ra below about 0.3 nm, as measured by Atomic Force Microscopy (AFM).
    Type: Grant
    Filed: September 17, 2003
    Date of Patent: February 13, 2007
    Assignee: Seagate Technology LLC
    Inventors: Qixu David Chen, Thomas P. Nolan, Zhong Stella Wu, Samuel Dacke Harkness, IV, Rajiv Yadav Ranjan
  • Patent number: 7169488
    Abstract: A granular perpendicular magnetic recording medium having a surface treated magnetic layer comprising an oxidized or nitrogenized boundary layer formed on the surface of the magnetic layer, wherein the magnetic layer comprises granular magnetic regions having oxygen and/or nitrogen-containing grain boundaries. In one embodiment, the granular perpendicular recording medium further comprises a soft magnetic layer below the surface treated granular magnetic layer and a protective overcoat over the surface treated granular magnetic layer. A method of manufacturing a granular perpendicular magnetic recording medium includes depositing a magnetic layer having granular structure over a substrate and subsequently surface treating the granular magnetic layer in an oxygen and/or nitrogen-containing atmosphere to produce an oxidized and/or nitrogenized boundary layer formed on the surface of the granular magnetic layer.
    Type: Grant
    Filed: November 10, 2003
    Date of Patent: January 30, 2007
    Assignee: Seagate Technology LLC
    Inventors: Qixu Chen, Tom Nolan, Raj Nagappan Thangaraj, Zhong (Stella) Wu, Samuel Dacke Harkness
  • Patent number: 7105240
    Abstract: A perpendicular recording medium having a magnetic layer comprising cobalt, platinum, and at least one of molybdenum and chromium. In a preferred embodiment, the perpendicular recording medium comprises granular magnetic regions having oxygen-containing grain boundaries. The magnetic layer of the present invention preferably exhibits improved corrosion resistance while maintaining the magnetic properties suitable for high density perpendicular recording.
    Type: Grant
    Filed: December 19, 2003
    Date of Patent: September 12, 2006
    Assignee: Seagate Technology LLC
    Inventors: Zhong (Stella) Wu, Raj Nagappan Thangaraj, Samuel Dacke Harkness
  • Publication number: 20060121319
    Abstract: Disclosed are granular magnetic recording media with improved grain segregation and corrosion resistance, comprising a non-magnetic substrate and at least one granular magnetic recording layer formed over the surface, comprised of at least one ferromagnetic material including magnetic grains with grain boundaries and a non-magnetic material comprised of a mixture of metal oxides. Also disclosed are methods for fabricating the improved media.
    Type: Application
    Filed: December 6, 2004
    Publication date: June 8, 2006
    Inventors: Zhong (Stella) Wu, Samuel Harkness
  • Patent number: 7026010
    Abstract: Laminated magnetic recording medium with two Co-containing layers separated by a non-magnetic Ru-containing interlayer is stabilized by Ru-containing layer between the recording layers and Co-containing stabilization layers through anti-ferromagnetic coupling. The insertion of Co layer beneath Ru spacer has resulted in increased coupling, and further coupling enhancement is achieved by low pressure process of Co and Ru layers.
    Type: Grant
    Filed: March 25, 2004
    Date of Patent: April 11, 2006
    Assignee: Seagate Technology LLC
    Inventors: Zhong Stella Wu, Samuel Dacke Harkness