Patents Represented by Attorney Thomas Berthold
  • Patent number: 6771534
    Abstract: A method and structure for a non-volatile magnetic random access memory (MRAM) device that has a stable magnetic electrode, an oxide layer adjacent the stable magnetic electrode, and a free magnetic electrode. The oxide layer is between the stable magnetic electrode and the free magnetic electrode. In the invention, a conductor is connected to a stable magnetic electrode. The oxide layer has a resistance at levels to allow sufficient power dissipation to lower the anisotropy of the free magnetic electrode through current induced heating. Current-induced heating is used in combination with spin-transfer torque or a magnetic field to switch the free magnetic electrode.
    Type: Grant
    Filed: November 15, 2002
    Date of Patent: August 3, 2004
    Assignee: International Business Machines Corporation
    Inventor: Barry C. Stipe
  • Patent number: 4853810
    Abstract: The method involves the steps of moving the magnetic head (8) to within aerodynamic distance from the electrically conductive surface (16) of rotating magnetic recording disk, further positioning of the head (8) until a tunnel current occurs across the gap between the head (8) and surface (16), and maintaining said tunnel current constant by using the deviations of the current from a predetermined value corresponding to a certain flying height.The apparatus comprises a tunnel electrode (9) forming an integral part of the head assembly which is attached to a distance control mechanism (5) permitting the positioning of the head assembly with a one-nanometer accuracy. The tunnel electrode (9) has a very slightly beveled shoulder (45, 47) ensuring early detection of asperities approaching the head. Gradation of the potential between tunnel electrode (9) and surface (16) of the recording disk (3) is used to enhance the response to asperities.
    Type: Grant
    Filed: November 23, 1987
    Date of Patent: August 1, 1989
    Assignee: International Business Machines Corporation
    Inventors: Wolfgang D. Pohl, James K. Gimzewski, Paul R. Muralt