Patents by Inventor Jumna P. Ramdular

Jumna P. Ramdular 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: 6842308
    Abstract: A head for a magnetic drive that includes a substrate with a thermal expansion rate CTE1. A transducer in the head has a bond to the substrate and has a transducer thermal expansion rate CTE2 that is greater than CTE1. A restraint layer in the substrate has a bond to one side of the transducer and has a first restraint layer thermal expansion rate CTE3 that is lower than CTE1. The restraint layer restrains protrusion of the transducer beyond the substrate at higher operating temperatures.
    Type: Grant
    Filed: April 30, 2001
    Date of Patent: January 11, 2005
    Assignee: Seagate Technology LLC
    Inventors: Ladislav R. Pust, Youping Mei, Sunita Gangopadhyay, Jumna P. Ramdular, Mallika Kamarajugadda
  • Patent number: 6756287
    Abstract: A method is used for forming sliders for use in a disc drive actuation system. The method comprises providing a wafer formed of a substrate having a base coat and an overcoat. Wafer-level notch lanes having a first width extend across the wafer in a first direction. The overcoat is removed from the wafer-level notch lanes. The wafer is sliced along a portion of the wafer-level lanes through the base coat to form a channel. The wafer is mechanically sliced through the substrate along slice lanes that extend across the wafer in the first direction to differentiate the wafer into bars. The bars are cut in a second direction substantially perpendicular to the first direction to form the sliders.
    Type: Grant
    Filed: March 7, 2002
    Date of Patent: June 29, 2004
    Assignee: Seagate Technology LLC
    Inventors: Mohamed Salah H. Khlif, Gordon M. Jones, Paul E. Gallup, Jumna P. Ramdular
  • Patent number: 6700752
    Abstract: A read/write head with a bottom shield on a slider substrate and a shared shield spaced apart from the bottom shield. A write head is deposited on the shared shield. A read sensor is spaced apart by reader magnetic gaps from the bottom shield and the shared shield. Electrically insulating layers in the reader magnetic gaps form a thermal resistance between the read sensor and the shields. A thermally conducting nonmagnetic layer in a reader magnetic gap reduces the thermal resistance without a corresponding reduction in the reader magnetic gaps.
    Type: Grant
    Filed: March 27, 2002
    Date of Patent: March 2, 2004
    Assignee: Seagate Technology LLC
    Inventors: Dimitar Dimitrov, Michael C. Kautzky, Sunita B. Gangopadhyay, Jumna P. Ramdular, Sisavath M. Bounnakhom, I-Fei Tsu, Robert W. Lamberton
  • Publication number: 20030013227
    Abstract: A method is used for forming sliders for use in a disc drive actuation system. The method comprises providing a wafer formed of a substrate having a base coat and an overcoat. Wafer-level notch lanes having a first width extend across the wafer in a first direction. The overcoat is removed from the wafer-level notch lanes. The wafer is sliced along a portion of the wafer-level lanes through the base coat to form a channel. The wafer is mechanically sliced through the substrate along slice lanes that extend across the wafer in the first direction to differentiate the wafer into bars. The bars are cut in a second direction substantially perpendicular to the first direction to form the sliders.
    Type: Application
    Filed: March 7, 2002
    Publication date: January 16, 2003
    Applicant: Seagate Technology LLC
    Inventors: Mohamed Salah H. Khlif, Gordon M. Jones, Paul E. Gallup, Jumna P. Ramdular, Ruperta T. Ramdular
  • Publication number: 20020154451
    Abstract: A read/write head with a bottom shield on a slider substrate and a shared shield spaced apart from the bottom shield. A write head is deposited on the shared shield. A read sensor is spaced apart by reader magnetic gaps from the bottom shield and the shared shield. Electrically insulating layers in the reader magnetic gaps form a thermal resistance between the read sensor and the shields. A thermally conducting nonmagnetic layer in a reader magnetic gap reduces the thermal resistance without a corresponding reduction in the reader magnetic gaps.
    Type: Application
    Filed: March 27, 2002
    Publication date: October 24, 2002
    Inventors: Dimitar V. Dimitrov, Michael C. Kautzky, Sunita B. Gangopadhyay, Jumna P. Ramdular, Sisavath M. Bounnakhom, I-Fei Tsu, Robert W. Lamberton
  • Patent number: 6462919
    Abstract: A spin valve sensor is disclosed that comprises a first layer of ferromagnetic material and a second layer of ferromagnetic material. A first layer of non-ferromagnetic material is positioned between the first and second layers of ferromagnetic material. A pinning layer is positioned adjacent to the first layer of ferromagnetic material such that the pinning layer is in contact with the first layer of ferromagnetic material. The spin valve includes synthetic antiferromagnetic bias means extending over passive end regions of the second layer of ferromagnetic material for producing a longitudinal bias in the passive end regions of a level sufficient to maintain the passive end regions in a single domain state. A method for forming a spin valve sensor with exchange tabs is also disclosed.
    Type: Grant
    Filed: November 18, 1999
    Date of Patent: October 8, 2002
    Assignee: Seagate Technology LLC
    Inventors: Anthony M. Mack, Sining Mao, Michael A. Seigler, Nurul Amin, Taras G. Pokhil, Ananth Naman, Jin Li, Zheng Gao, Edward S. Murdock, Jumna P. Ramdular, Timothy Radke
  • Publication number: 20020057531
    Abstract: A method is used for aligning a slider on a gimbal. The gimbal includes a slider opposing face with a flex circuit material on the slider opposing face and a flex on suspension (FOS) bond pad is disposed on the flex circuit material. The slider has a gimbal opposing face and a disc opposing face. Both faces are bounded by a leading edge and a trailing edge. The slider has a forward face along the trailing edge extending between the gimbal opposing face and the disc opposing face. An extended bond pad is formed on the forward face of the slider. A notch is formed on the slider in the forward face adjacent the gimbal opposing face. The slider is placed on the flex circuit material such that the extended bond pad is positioned relative to the FOS bond pad to improve bond strength and static attitude.
    Type: Application
    Filed: November 13, 2001
    Publication date: May 16, 2002
    Applicant: Seagate Technology LLC
    Inventors: Richard L. Segar, Jumna P. Ramdular, Ruperta T. Randular, Paul E. Gallup, John A. Rice, Richard P. Larson, Michael J. Gronseth, Gordon M. Jones
  • Patent number: 5712565
    Abstract: A magnetoresistive sensor (10) having permanent magnet stabilization includes a magnetoresistive layer (12), at least one permanent magnet (14a or 14b), and first and second current contacts (16a and 16b). The magnetoresistive layer (12) has an active sensing region (18) having a first thickness, and at least one under layer region (26a or 26b), with each under layer region (26a or 26b) having a second thickness that is less than the first thickness. Each permanent magnet (14a or 14b) is formed upon an under layer region (26a or 26b) of the magnetoresistive layer (12), and the first and second contacts (16a and 16b) are electrically coupled to the active region (18).
    Type: Grant
    Filed: September 13, 1994
    Date of Patent: January 27, 1998
    Assignee: Seagate Technology, Inc.
    Inventors: Allan E. Schultz, Peter K. George, Arthur Calderon, Jumna P. Ramdular, Juan J. Fernandez-De Castro, Leroy L. Longworth, Peter I. Bonyhard