Patents by Inventor Raj Nagappan Thangaraj

Raj Nagappan Thangaraj 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).

  • Perpendicular media with Cr-doped Fe-alloy containing soft underlayer (SUL)
    Patent number: 8313848
    Abstract: A perpendicular magnetic recording medium having a substrate, a Cr-doped Fe-alloy-containing underlayer containing about 8 to 18 at % Cr and a perpendicular recording magnetic layer, and a process for improving corrosion resistance of the recording medium and for manufacturing the recording medium are disclosed.
    Type: Grant
    Filed: August 15, 2011
    Date of Patent: November 20, 2012
    Assignee: Seagate Technology LLC
    Inventors: Raj Nagappan Thangaraj, Mariana Rodica Munteanu, Erol Girt, Michael J. Stirniman, Thomas Patrick Nolan
  • Perpendicular Media with Cr-Doped Fe-Alloy Containing Soft Underlayer (SUL)
    Publication number: 20120070694
    Abstract: A perpendicular magnetic recording medium having a substrate, a Cr-doped Fe-alloy-containing underlayer containing about 8 to 18 at % Cr and a perpendicular recording magnetic layer, and a process for improving corrosion resistance of the recording medium and for manufacturing the recording medium are disclosed.
    Type: Application
    Filed: August 15, 2011
    Publication date: March 22, 2012
    Applicant: SEAGATE TECHNOLOGY LLC
    Inventors: Raj Nagappan Thangaraj, Mariana Rodica Munteanu, Erol Girt, Michael J. Stirniman, Thomas Patrick Nolan
  • Perpendicular media with Cr-doped Fe-alloy-containing soft underlayer (SUL)
    Patent number: 7998606
    Abstract: A perpendicular magnetic recording medium having a substrate, a Cr-doped Fe-alloy-containing underlayer containing about 8 to 18 at % Cr and a perpendicular recording magnetic layer, and a process for improving corrosion resistance of the recording medium and for manufacturing the recording medium are disclosed.
    Type: Grant
    Filed: July 27, 2009
    Date of Patent: August 16, 2011
    Assignee: Seagate Technology LLC
    Inventors: Raj Nagappan Thangaraj, Mariana Rodica Munteanu, Erol Girt, Michael J. Stirniman, Thomas Patrick Nolan
  • PERPENDICULAR MEDIA WITH Cr-DOPED Fe-ALLOY-CONTAINING SOFT UNDERLAYER (SUL) FOR IMPROVED CORROSION PERFORMANCE
    Publication number: 20100081012
    Abstract: A perpendicular magnetic recording medium having a substrate, a Cr-doped Fe-alloy-containing underlayer containing about 8 to 18 at % Cr and a perpendicular recording magnetic layer, and a process for improving corrosion resistance of the recording medium and for manufacturing the recording medium are disclosed.
    Type: Application
    Filed: July 27, 2009
    Publication date: April 1, 2010
    Applicant: Seagate Technology LLC
    Inventors: Raj Nagappan Thangaraj, Mariana Rodica Munteanu, Erol Girt, Michael J. Stirniman, Thomas Patrick Nolan
  • Perpendicular media with Cr-doped Fe-alloy-containing soft underlayer (SUL) for improved corrosion performance
    Patent number: 7566508
    Abstract: A perpendicular magnetic recording medium having a substrate, a Cr-doped Fe-alloy-containing underlayer containing about 8 to 18 at % Cr and a perpendicular recording magnetic layer, and a process for improving corrosion resistance of the recording medium and for manufacturing the recording medium are disclosed.
    Type: Grant
    Filed: March 2, 2005
    Date of Patent: July 28, 2009
    Assignee: Seagate Technology LLC
    Inventors: Raj Nagappan Thangaraj, Mariana Rodica Munteanu, Erol Girt, Michael Joseph Stirniman
  • Granular perpendicular media with surface treatment for improved magnetic properties and corrosion resistance
    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
  • Perpendicular media with improved corrosion performance
    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
  • Perpendicular media with improved corrosion performance
    Publication number: 20040247942
    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: Application
    Filed: December 19, 2003
    Publication date: December 9, 2004
    Applicant: SEAGATE TECHNOLOGY LLC
    Inventors: Zhong (Stella) Wu, Raj Nagappan Thangaraj, Samuel Dacke Harkness
  • Granular perpendicular media with surface treatment for improved magnetic properties and corrosion resistance
    Publication number: 20040247941
    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: Application
    Filed: November 10, 2003
    Publication date: December 9, 2004
    Inventors: Qixu Chen, Tom Nolan, Raj Nagappan Thangaraj, Zhong Stella Wu, Samuel Dacke Harkness