Patents by Inventor Stuart Stephen Papworth Parkin

Stuart Stephen Papworth Parkin 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).

  • Magnetic memory array using magnetic tunnel junction devices in the memory cells
    Patent number: 5640343
    Abstract: A nonvolatile magnetic random access memory (MRAM) is an array of individual magnetic memory cells. Each memory cell is a magnetic tunnel junction (MTJ) element and a diode electrically connected in series. Each MTJ is formed of a pinned ferromagnetic layer whose magnetization direction is prevented from rotating, a free ferromagnetic layer whose magnetization direction is free to rotate between states of parallel and antiparallel to the fixed magnetization of the pinned ferromagnetic layer, and an insulating tunnel barrier between and in contact with the two ferromagnetic layers. Each memory cell has a high resistance that is achieved in a very small surface area by controlling the thickness, and thus the electrical barrier height, of the tunnel barrier layer.
    Type: Grant
    Filed: March 18, 1996
    Date of Patent: June 17, 1997
    Assignee: International Business Machines Corporation
    Inventors: William Joseph Gallagher, James Harvey Kaufman, Stuart Stephen Papworth Parkin, Roy Edwin Scheuerlein