Patents by Inventor Wonjoon Jung

Wonjoon Jung 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).

  • Publication number: 20260076096
    Abstract: A memory device includes a magnetoresistive memory cell which contains a first terminal electrode, a second terminal electrode, and a double magnetic tunnel junction located between the first terminal electrode and the second terminal electrode. The double magnetic tunnel junction includes, from bottom to top, a bottom synthetic antiferromagnet (SAF) structure including a barrier-contacting bottom ferromagnetic layer, a first tunneling barrier layer, a common free layer, a second tunneling barrier layer, and a top SAF structure including a barrier-contacting top ferromagnetic layer in antiparallel alignment with the barrier-contacting bottom ferromagnetic layer. The bottom SAF structure is different from the top SAF structure.
    Type: Application
    Filed: September 11, 2024
    Publication date: March 12, 2026
    Inventors: Wonjoon JUNG, Goran MIHAJLOVIC, Rajesh CHOPDEKAR, Nathan FRANKLIN
  • Publication number: 20250384926
    Abstract: A magnetoresistive memory cell includes a magnetic polarizer layer having a hard magnetization along a hard magnetization direction, a first magnetic tunnel junction located on a first side of the magnetic polarizer layer and including a first reference layer having a first side facing the magnetic polarizer layer, a first free layer facing a second side of the first reference layer, and a first tunnel barrier layer located between the first free layer and the first reference layer. The memory cell also includes a second magnetic tunnel junction located on a second side of the magnetic polarizer layer and including a second reference layer having a second side facing the magnetic polarizer layer, a second free layer facing a first side of the second reference layer, and a second tunnel barrier layer located between the second free layer and the second reference layer.
    Type: Application
    Filed: July 31, 2024
    Publication date: December 18, 2025
    Inventors: Goran MIHAJLOVIC, Wonjoon JUNG, Lei WAN, Nathan FRANKLIN
  • Publication number: 20250384909
    Abstract: A magnetoresistive memory cell includes a magnetic polarizer layer having a hard magnetization along a hard magnetization direction, a first magnetic tunnel junction located on a first side of the magnetic polarizer layer and including a first reference layer having a first side facing the magnetic polarizer layer, a first free layer facing a second side of the first reference layer, and a first tunnel barrier layer located between the first free layer and the first reference layer. The memory cell also includes a second magnetic tunnel junction located on a second side of the magnetic polarizer layer and including a second reference layer having a second side facing the magnetic polarizer layer, a second free layer facing a first side of the second reference layer, and a second tunnel barrier layer located between the second free layer and the second reference layer.
    Type: Application
    Filed: July 31, 2024
    Publication date: December 18, 2025
    Inventors: Lei WAN, Goran MIHAJLOVIC, Wonjoon JUNG, Noraica DAVILA MELENDEZ
  • Publication number: 20250386523
    Abstract: A tunneling barrier resistor includes a first electrode layer containing a first nonmagnetic iron-group-containing alloy layer which includes a first refractory metal, a second electrode layer containing a second nonmagnetic iron-group-containing alloy layer which includes a second refractory metal, and a first tunneling barrier dielectric layer located between the first electrode layer and the second electrode layer.
    Type: Application
    Filed: July 16, 2024
    Publication date: December 18, 2025
    Inventors: Wonjoon JUNG, Michael GROBIS, Lei WAN, Hans RICHTER, James REINER, Tiffany SANTOS
  • Publication number: 20250380616
    Abstract: A spin transfer torque (STT) magnetoresistive memory cell includes a magnetic tunnel junction including a reference layer, a free layer, and a nonmagnetic tunnel barrier located between the reference layer and the free layer, and perpendicular exchange bias layer in contact with the free layer.
    Type: Application
    Filed: July 23, 2024
    Publication date: December 11, 2025
    Inventors: Goran MIHAJLOVIC, Wonjoon JUNG
  • Publication number: 20250285669
    Abstract: A magnetoresistive memory cell includes a first electrode; a second electrode; and a layer stack located between the first electrode and the second electrode and comprising, from one end to another, a first reference layer, a first tunnel barrier layer, a free layer, a second tunnel barrier layer, and a second reference layer. A first one of the first reference layer and the second reference layer comprises a positive spin polarization material. A second one of the first reference layer and the second reference layer comprises a negative spin polarization material. A magnetization direction of the second reference layer is parallel to a magnetization direction of the first reference layer.
    Type: Application
    Filed: March 8, 2024
    Publication date: September 11, 2025
    Inventors: Goran MIHAJLOVIC, Wonjoon JUNG
  • Patent number: 11361805
    Abstract: A memory device includes a first electrode, a second electrode that is spaced from the first electrode, a fixed vertical magnetization structure configured to generate a fixed vertical magnetic field and located between the first electrode and the second electrode, at least one layer stack located between the fixed magnetization structure and the second electrode and containing respective spacer dielectric layer and a respective additional reference layer including a respective ferromagnetic material having perpendicular magnetic anisotropy, and a magnetic tunnel junction located between the at least one layer stack and the second electrode, the magnetic tunnel junction containing a reference layer, a free layer, and a nonmagnetic tunnel barrier layer located between the reference layer and the free layer, and the reference layer being more proximal to the at least one layer stack than the free layer is to the at least one layer stack.
    Type: Grant
    Filed: March 16, 2021
    Date of Patent: June 14, 2022
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Goran Mihajlovic, Wonjoon Jung, Bhagwati Prasad
  • Publication number: 20210389387
    Abstract: A magnetic sensor comprising a first shield and a second shield and a sensor stack between the first and the second shield, the sensor stack having a plurality of layers wherein at least one layer is annealed using in-situ rapid thermal annealing. In one implementation of the magnetic sensor a seed layer is annealed using in-situ rapid thermal annealing. Alternatively, one of a barrier layer, an antiferromagnetic (AFM) layer, and a cap layer is annealed using in-situ rapid thermal annealing.
    Type: Application
    Filed: August 27, 2021
    Publication date: December 16, 2021
    Inventors: Qing HE, Wonjoon JUNG, Mark William COVINGTON, Mark Thomas KIEF, Yonghua CHEN
  • Patent number: 11152047
    Abstract: A magnetic memory device contains a synthetic antiferromagnetic (SAF) structure that includes an antiferromagnetically coupled stack and a reference layer. The antiferromagnetically coupled stack contains plural multilayer stacks. Each multilayer stack contains at least one ferromagnetic material layer, a non-magnetic layer and a non-magnetic SAF spacer layer having a different composition than the non-magnetic layer.
    Type: Grant
    Filed: October 23, 2019
    Date of Patent: October 19, 2021
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Wonjoon Jung, Michael Nicolas Albert Tran
  • Patent number: 11125836
    Abstract: A magnetic sensor comprising a first shield and a second shield and a sensor stack between the first and the second shield, the sensor stack having a plurality of layers wherein at least one layer is annealed using in-situ rapid thermal annealing. In one implementation of the magnetic sensor a seed layer is annealed using in-situ rapid thermal annealing. Alternatively, one of a barrier layer, an antiferromagnetic (AFM) layer, and a cap layer is annealed using in-situ rapid thermal annealing.
    Type: Grant
    Filed: December 29, 2017
    Date of Patent: September 21, 2021
    Assignee: SEAGATE TECHNOLOGY LLC
    Inventors: Qing He, Wonjoon Jung, Mark William Covington, Mark Thomas Kief, Yonghua Chen
  • Publication number: 20210225421
    Abstract: A memory device includes a first electrode, a second electrode that is spaced from the first electrode, a fixed vertical magnetization structure configured to generate a fixed vertical magnetic field and located between the first electrode and the second electrode, at least one layer stack located between the fixed magnetization structure and the second electrode and containing respective spacer dielectric layer and a respective additional reference layer including a respective ferromagnetic material having perpendicular magnetic anisotropy, and a magnetic tunnel junction located between the at least one layer stack and the second electrode, the magnetic tunnel junction containing a reference layer, a free layer, and a nonmagnetic tunnel barrier layer located between the reference layer and the free layer, and the reference layer being more proximal to the at least one layer stack than the free layer is to the at least one layer stack.
    Type: Application
    Filed: March 16, 2021
    Publication date: July 22, 2021
    Inventors: Goran MIHAJLOVIC, Wonjoon JUNG, Bhagwati PRASAD
  • Publication number: 20210125650
    Abstract: A magnetic memory device contains a synthetic antiferromagnetic (SAF) structure that includes an antiferromagnetically coupled stack and a reference layer. The antiferromagnetically coupled stack contains plural multilayer stacks. Each multilayer stack contains at least one ferromagnetic material layer, a non-magnetic layer and a non-magnetic SAF spacer layer having a different composition than the non-magnetic layer.
    Type: Application
    Filed: October 23, 2019
    Publication date: April 29, 2021
    Inventors: Wonjoon JUNG, Michael Nicolas Albert TRAN
  • Patent number: 10121499
    Abstract: A read sensor that includes a free layer having a magnetization that changes according to an external magnetic field. The read sensor also includes an additional magnetic layer and a non-magnetic layer. The non-magnetic layer may include a corrugated surface facing the additional magnetic layer. The corrugated surface is configured to enhance uniaxial anisotropy in the read sensor.
    Type: Grant
    Filed: June 9, 2017
    Date of Patent: November 6, 2018
    Assignee: Seagate Technology LLC
    Inventors: Sameh Hassan, Wonjoon Jung, Mark Kief, Marcus Ormston
  • Publication number: 20180120387
    Abstract: A magnetic sensor comprising a first shield and a second shield and a sensor stack between the first and the second shield, the sensor stack having a plurality of layers wherein at least one layer is annealed using in-situ rapid thermal annealing. In one implementation of the magnetic sensor a seed layer is annealed using in-situ rapid thermal annealing. Alternatively, one of a barrier layer, an antiferromagnetic (AFM) layer, and a cap layer is annealed using in-situ rapid thermal annealing.
    Type: Application
    Filed: December 29, 2017
    Publication date: May 3, 2018
    Inventors: Qing He, Wonjoon Jung, Mark William Covington, Mark Thomas Kief, Yonghua Chen
  • Patent number: 9880232
    Abstract: A magnetic sensor comprising a first shield and a second shield and a sensor stack between the first and the second shield, the sensor stack having a plurality of layers wherein at least one layer is annealed using in-situ rapid thermal annealing. In one implementation of the magnetic sensor a seed layer is annealed using in-situ rapid thermal annealing. Alternatively, one of a barrier layer, an antiferromagnetic (AFM) layer, and a cap layer is annealed using in-situ rapid thermal annealing.
    Type: Grant
    Filed: March 14, 2012
    Date of Patent: January 30, 2018
    Assignee: SEAGATE TECHNOLOGY LLC
    Inventors: Qing He, Wonjoon Jung, Mark William Covington, Mark Thomas Kief, Yonghua Chen
  • Patent number: 9812157
    Abstract: A lateral spin valve reader and fabrication method thereof. The method includes forming an injector, a detector and a common channel layer that extends from the injector to the detector. The method also includes forming a first channel layer between the common channel layer and at least one of the injector or the detector with the first channel layer in contact with the common channel layer, thereby providing an interface between the first channel layer and the common channel layer.
    Type: Grant
    Filed: March 6, 2017
    Date of Patent: November 7, 2017
    Assignee: Seagate Technology LLC
    Inventors: Wonjoon Jung, Thomas Roy Boonstra, Sung-Hoon Gee, David A. Deen
  • Publication number: 20170278529
    Abstract: A read sensor that includes a free layer having a magnetization that changes according to an external magnetic field. The read sensor also includes an additional magnetic layer and a non-magnetic layer. The non-magnetic layer may include a corrugated surface facing the additional magnetic layer. The corrugated surface is configured to enhance uniaxial anisotropy in the read sensor.
    Type: Application
    Filed: June 9, 2017
    Publication date: September 28, 2017
    Inventors: Sameh Hassan, Wonjoon Jung, Mark Kief, Marcus Ormston
  • Patent number: 9691417
    Abstract: A reader includes a bearing surface, a sensor stack and a bottom shield below the sensor stack. The bottom shield has a synthetic antiferromagnetic (SAF) structure that includes a first magnetic layer that has a first width at the bearing surface and a second magnetic layer that has a second width at the bearing surface. The second width is less than the first width. The second magnetic layer has a magnetic orientation with at least a component that is substantially orthogonal to the bearing surface.
    Type: Grant
    Filed: October 28, 2015
    Date of Patent: June 27, 2017
    Assignee: Seagate Technology LLC
    Inventors: Wonjoon Jung, Victor Sapozhnikov
  • Patent number: 9679589
    Abstract: A read sensor that includes a free layer having a magnetization that changes according to an external magnetic field. The read sensor also includes an additional magnetic layer and a non-magnetic layer. The non-magnetic layer may include a corrugated surface facing the additional magnetic layer. The corrugated surface is configured to enhance uniaxial anisotropy in the read sensor.
    Type: Grant
    Filed: September 11, 2015
    Date of Patent: June 13, 2017
    Assignee: Seagate Technology LLC
    Inventors: Sameh Hassan, Wonjoon Jung, Mark Kief, Marcus Ormston
  • Publication number: 20170076743
    Abstract: A read sensor that includes a free layer having a magnetization that changes according to an external magnetic field. The read sensor also includes an additional magnetic layer and a non-magnetic layer. The non-magnetic layer may include a corrugated surface facing the additional magnetic layer. The corrugated surface is configured to enhance uniaxial anisotropy in the read sensor.
    Type: Application
    Filed: September 11, 2015
    Publication date: March 16, 2017
    Inventors: Sameh Hassan, Wonjoon Jung, Mark Kief, Marcus Ormston