Patents by Inventor Daniel Bedau

Daniel Bedau 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: 9721636
    Abstract: A method and apparatus for controlled switching of a magnetoresistive random access memory device is disclosed herein. The method includes delivering a current to a magnetoresistive random access memory device, wherein the MRAM device is in a first state, measuring a voltage drop across the magnetoresistive random access memory device in real-time with a resistance detector, wherein a voltage drop beyond a threshold voltage equates to switching from a first state to a second state, the first state different from the second state, determining whether the MRAM device has switched from the first state to the second state, and stopping the current delivered to the magnetoresistive random access memory device.
    Type: Grant
    Filed: January 28, 2016
    Date of Patent: August 1, 2017
    Assignee: Western Digital Technologies, Inc.
    Inventors: Daniel Bedau, Patrick M. Braganca, Kurt Allan Rubin
  • Patent number: 9711718
    Abstract: The present disclosure generally relates to an apparatus for a three terminal nonvolatile memory cell. Specifically, a three terminal nonvolatile bipolar junction transistor. The bipolar junction memory device includes a collector layer, a base layer disposed on the collector layer, an emitter layer disposed on the base layer, and a conductive anodic filament extending from the collector layer to the base layer. As current is applied to the transistor and a voltage is applied between P-N junction of the collector layer and the base layer, a conductive anodic filament (CAF) forms. The CAF is non-volatile and short circuits the reverse-biased P-N junction barrier thus keeping the device in a low-resistive state. Removing the CAF switches the device back to a high resistive state. Thus, a new type of semiconductor device advantageously combines computation and memory to form a flux-linkage modulated memory cell.
    Type: Grant
    Filed: April 28, 2016
    Date of Patent: July 18, 2017
    Assignee: Western Digital Technologies, Inc.
    Inventor: Daniel Bedau
  • Publication number: 20170133588
    Abstract: Embodiments disclosed herein generally relate to an electrode structure for a resistive random access memory (ReRAM) device cell which focuses the electric field at a center of the cell and methods for making the same. As such, a non-uniform metallic electrode may be deposited onto the ReRAM device which is subsequently exposed to an oxidation or nitrogenation process during cell fabrication. The electrode structure may be conical or pyramid shaped, and comprise at least one layer comprising a first material and a second material, wherein the concentration of the first material and the second material are varied based on location within the electrode. A metal electrode profile is formed which favors the center of the cell as the location with the greatest electric field. As such, size scaling and reliability of the non-volatile memory component are each increased.
    Type: Application
    Filed: November 6, 2015
    Publication date: May 11, 2017
    Inventors: Daniel BEDAU, Jeffrey Robinson CHILDRESS, Oleksandr MOSENDZ, John C. READ, Derek STEWART
  • Patent number: 9449668
    Abstract: A high speed, low power method to control and switch the magnetization direction of a magnetic region in a magnetic device for memory cells using spin polarized electrical current. The magnetic device comprises a pinned magnetic layer, a reference magnetic layer with a fixed magnetization direction and a free magnetic layer with a changeable magnetization direction. The magnetic layers are separated by insulating non-magnetic layers. A current can be applied to the device to induce a torque that alters the magnetic state of the device so that it can act as a magnetic memory for writing information. The resistance, which depends on the magnetic state of the device, can be measured to read out the information stored in the device.
    Type: Grant
    Filed: July 7, 2015
    Date of Patent: September 20, 2016
    Assignee: New York University
    Inventors: Andrew Kent, Daniel Bedau, Huanlong Liu
  • Patent number: 9236103
    Abstract: A magnetic device includes a magnetized polarizing layer, a free magnetic layer, and a reference layer. The free magnetic layer forms a first electrode and is separated from the magnetized polarizing layer by a first non-magnetic metal layer. The free magnetic layer has a magnetization vector having a first and second stable state. The reference layer forms a second electrode and is separated from the free-magnetic layer by a second non-magnetic layer. Unipolar current is sourced through the polarizing, free magnetic and reference layers. Switching of the magnetization vector of the free magnetic layer from the first stable state to the second state is initiated by application of a first unipolar current pulse, and switching of the magnetization vector of the free magnetic layer from the second stable state to the first stable state is initiated by application of a second unipolar current pulse.
    Type: Grant
    Filed: April 29, 2014
    Date of Patent: January 12, 2016
    Assignee: New York University
    Inventors: Andrew Kent, Daniel Bedau, Huanlong Liu
  • Publication number: 20150357015
    Abstract: A high speed, low power method to control and switch the magnetization direction of a magnetic region in a magnetic device for memory cells using spin polarized electrical current. The magnetic device comprises a pinned magnetic layer, a reference magnetic layer with a fixed magnetization direction and a free magnetic layer with a changeable magnetization direction. The magnetic layers are separated by insulating non-magnetic layers. A current can be applied to the device to induce a torque that alters the magnetic state of the device so that it can act as a magnetic memory for writing information. The resistance, which depends on the magnetic state of the device, can be measured to read out the information stored in the device.
    Type: Application
    Filed: July 7, 2015
    Publication date: December 10, 2015
    Applicant: NEW YORK UNIVERSITY
    Inventors: Andrew Kent, Daniel Bedau, Huanlong Liu
  • Patent number: 8941196
    Abstract: Orthogonal spin-torque bit cells whose spin torques from a perpendicular polarizer and an in-plane magnetized reference layer are constructively or destructively combined. An orthogonal spin-torque bit cell includes a perpendicular magnetized polarizing layer configured to provide a first spin-torque; an in-plane magnetized free layer and a reference layer configured to provide a second spin-torque. The first spin-torque and the second spin-torque combine and the combined first spin-torque and second spin-torque influences the magnetic state of the in-plane magnetized free layer. The in-plane magnetized free layer and the reference layer form a magnetic tunnel junction. The first spin-torque and second spin-torque can combine constructively to lower a switching current, increase a switching speed, and/or torque decrease an operating energy of the orthogonal spin-torque bit cell.
    Type: Grant
    Filed: July 3, 2013
    Date of Patent: January 27, 2015
    Assignee: New York University
    Inventors: Daniel Bedau, Huanlong Liu, Andrew David Kent
  • Publication number: 20140233306
    Abstract: A magnetic device includes a magnetized polarizing layer, a free magnetic layer, and a reference layer. The free magnetic layer forms a first electrode and is separated from the magnetized polarizing layer by a first non-magnetic metal layer. The free magnetic layer has a magnetization vector having a first and second stable state. The reference layer forms a second electrode and is separated from the free-magnetic layer by a second non-magnetic layer. Unipolar current is sourced through the polarizing, free magnetic and reference layers. Switching of the magnetization vector of the free magnetic layer from the first stable state to the second state is initiated by application of a first unipolar current pulse, and switching of the magnetization vector of the free magnetic layer from the second stable state to the first stable state is initiated by application of a second unipolar current pulse.
    Type: Application
    Filed: April 29, 2014
    Publication date: August 21, 2014
    Applicant: New York University
    Inventors: Andrew Kent, Daniel Bedau, Huanlong Liu
  • Patent number: 8755222
    Abstract: Orthogonal spin-transfer magnetic random access memory (OST-MRAM) uses a spin-polarizing layer magnetized perpendicularly to the free layer to achieve large spin-transfer torques and ultra-fast energy efficient switching. OST-MRAM devices that incorporate a perpendicularly magnetized spin-polarizing layer and a magnetic tunnel junction, which consists of an in-plane magnetized free layer and synthetic antiferromagnetic reference layer, exhibit improved performance over prior art devices. The switching is bipolar, occurring for positive and negative polarity pulses, consistent with a precessional reversal mechanism, and requires an energy less than 450 fJ and may be reliably observed at room temperature with 0.7 V amplitude pulses of 500 ps duration.
    Type: Grant
    Filed: November 16, 2011
    Date of Patent: June 17, 2014
    Assignee: New York University
    Inventors: Andrew Kent, Daniel Bedau, Huanlong Liu
  • Publication number: 20140015074
    Abstract: Orthogonal spin-torque bit cells whose spin torques from a perpendicular polarizer and an in-plane magnetized reference layer are constructively or destructively combined. An orthogonal spin-torque bit cell includes a perpendicular magnetized polarizing layer configured to provide a first spin-torque; an in-plane magnetized free layer and a reference layer configured to provide a second spin-torque. The first spin-torque and the second spin-torque combine and the combined first spin-torque and second spin-torque influences the magnetic state of the in-plane magnetized free layer. The in-plane magnetized free layer and the reference layer form a magnetic tunnel junction. The first spin-torque and second spin-torque can combine constructively to lower a switching current, increase a switching speed, and/or torque decrease an operating energy of the orthogonal spin-torque bit cell.
    Type: Application
    Filed: July 3, 2013
    Publication date: January 16, 2014
    Inventors: Daniel BEDAU, Huanlong LIU, Andrew David KENT
  • Publication number: 20120294078
    Abstract: Orthogonal spin-transfer magnetic random access memory (OST-MRAM) uses a spin-polarizing layer magnetized perpendicularly to the free layer to achieve large spin-transfer torques and ultra-fast energy efficient switching. OST-MRAM devices that incorporate a perpendicularly magnetized spin-polarizing layer and a magnetic tunnel junction, which consists of an in-plane magnetized free layer and synthetic antiferromagnetic reference layer, exhibit improved performance over prior art devices. The switching is bipolar, occurring for positive and negative polarity pulses, consistent with a precessional reversal mechanism, and requires an energy less than 450 fJ and may be reliably observed at room temperature with 0.7 V amplitude pulses of 500 ps duration.
    Type: Application
    Filed: November 16, 2011
    Publication date: November 22, 2012
    Inventors: Andrew Kent, Daniel Bedau, Huanlong Liu