Patents Represented by Attorney Brendan J. Hanley
  • Patent number: 6954340
    Abstract: A magnetic head for perpendicular recording on double layer media with suppressed side writing and controlled write width is disclosed. The present invention reduces the problem of side writing and controls the write width of the writing element by providing a writing element with a trailing edge sized dimensionally larger than the leading edge, side shields, and specifically spaced writing gaps placed at various distances between the write element and the side shields, return poles, and the main pole.
    Type: Grant
    Filed: April 1, 2002
    Date of Patent: October 11, 2005
    Assignee: Seagate Technology LLC
    Inventors: Alexander M. Shukh, Ned Tabat
  • Patent number: 6927951
    Abstract: A head gimbal assembly that includes a bleed resistor applied over a specified area of the reader, writer and ground leads in order to protect from ESD damage is disclosed. The present invention address the need for an ESD protection system that includes a consistent and secure connection with leads, that does not contaminate the drive environment and applies a consistent resistivity to both the reader and writer element by providing a head gimbal assembly with strategically placed bleed resistors that will protect the read element from transient charge produced any time during the fabrication, assembly, testing and shipment of the disc drive.
    Type: Grant
    Filed: April 2, 2002
    Date of Patent: August 9, 2005
    Assignee: Seagate Technology LLC
    Inventors: Marsha Huha, Kevin Schulz, Werner Weidemann
  • Patent number: 6923860
    Abstract: The present invention is a tunneling magnetoresistive (TMR) stack configured to operate in a current-perpendicular-to-plane (CPP) mode, wherein a sense current flows substantially perpendicular to a longitudinal plane of the barrier layer. The TMR stack has a plurality of layers including a barrier layer. The barrier layer may made of titanium and may be oxidized with an aggressive oxidation method, such as with UV illumination, for a predetermined time period. The barrier layer may be formed on a first ferromagnetic layer before oxidation, and then a second ferromagnetic layer may be formed on the oxidized barrier layer. The TMR stack exhibits an increased magnetoresistive (MR) ratio, a lower RA product, a higher breakdown voltage of the TMR stack, and greater thermal stability.
    Type: Grant
    Filed: March 27, 2003
    Date of Patent: August 2, 2005
    Assignee: Seagate Technology LLC
    Inventors: Brian W. Karr, Mark T. Kief, Janusz J. Nowak
  • Patent number: 6865040
    Abstract: A system and method for measuring the fly height of a head flying over a disc in a disc drive is disclosed. A head is vertically spaced from a rotating disc surface by an air bearing surface. The disc has one or more radial grooves in the surface of the disc. As the disc rotates, the radial grooves on the disc pass under the head and induce a perturbation in the signal. By measuring the perturbations in the signal caused by the grooves in the disc surface, and by processing the measurement signal, a vertical spacing signal proportional to the vertical spacing between the disc and the head can be obtained.
    Type: Grant
    Filed: December 21, 2001
    Date of Patent: March 8, 2005
    Assignee: Seagate Technology, LLC
    Inventors: Serge Jacques Fayeulle, Paul W. Smith