Patents by Inventor Guohan Hu

Guohan Hu 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: 9431600
    Abstract: A device includes a seed layer, a magnetic track layer disposed on the seed layer, an alloy layer disposed on the magnetic track layer, a tunnel barrier layer disposed on the alloy layer, a pinning layer disposed on the tunnel barrier layer, a synthetic antiferromagnetic layer spacer disposed on the pinning layer, a pinned layer disposed on the synthetic antiferromagnetic spacer layer and an antiferromagnetic layer disposed on the pinned layer, and another device includes a seed layer, an antiferromagnetic layer disposed on the seed layer, a pinned layer disposed on the antiferromagnetic layer, a synthetic antiferromagnetic layer spacer disposed on the pinned layer, a pinning layer disposed on the synthetic antiferromagnetic layer spacer, a tunnel barrier layer disposed on the pinning layer, an alloy layer disposed on the tunnel barrier layer and a magnetic track layer disposed on alloy layer.
    Type: Grant
    Filed: October 6, 2014
    Date of Patent: August 30, 2016
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Guohan Hu, Cheng-Wei Chien
  • Patent number: 9391266
    Abstract: A magnetic material includes a cobalt layer between opposing iron layers. The iron layers include iron and are body-centered cubic (BCC), the cobalt layer comprises cobalt and is BCC or amorphous, and the magnetic material has a perpendicular magnetic anisotropy (PMA).
    Type: Grant
    Filed: March 26, 2015
    Date of Patent: July 12, 2016
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Guohan Hu, Daniel C. Worledge
  • Publication number: 20160190434
    Abstract: A mechanism relates to magnetic random access memory (MRAM). A free magnetic layer is provided and first fixed layers are disposed above the free magnetic layer. Second fixed layers are disposed below the free magnetic layer. The first fixed layers and the second fixed layers both comprise a rare earth element.
    Type: Application
    Filed: December 29, 2014
    Publication date: June 30, 2016
    Inventors: Guohan Hu, Daniel C. Worledge
  • Publication number: 20160190436
    Abstract: A mechanism relates to magnetic random access memory (MRAM). A free magnetic layer is provided and first fixed layers are disposed above the free magnetic layer. Second fixed layers are disposed below the free magnetic layer. The first fixed layers and the second fixed layers both comprise a rare earth element.
    Type: Application
    Filed: February 26, 2016
    Publication date: June 30, 2016
    Inventors: Guohan Hu, Daniel C. Worledge
  • Publication number: 20160190437
    Abstract: Embodiments are directed to a magnetic tunnel junction (MTJ) memory cell that includes a reference layer formed from a perpendicular magnetic anisotropy (PMA) reference layer and an interfacial reference layer. The MTJ further includes a free layer and a tunnel barrier positioned between the interfacial reference layer and the free layer. The tunnel barrier is configured to enable electrons to tunnel through the tunnel barrier between the interfacial reference layer and the free layer. A first in-situ alignment is provided between a tunnel barrier lattice structure of the tunnel barrier and an interfacial reference layer lattice structure of the interfacial reference layer. A second in-situ alignment is provided between the tunnel barrier lattice structure of the tunnel barrier and a free layer lattice structure of the free layer. The PMA reference layer lattice structure is not aligned with the interfacial reference layer lattice structure.
    Type: Application
    Filed: March 7, 2016
    Publication date: June 30, 2016
    Inventors: Guohan Hu, Daniel C. Worledge
  • Publication number: 20160190435
    Abstract: Embodiments are directed to a magnetic tunnel junction (MTJ) memory cell that includes a reference layer formed from a perpendicular magnetic anisotropy (PMA) reference layer and an interfacial reference layer. The MTJ further includes a free layer and a tunnel barrier positioned between the interfacial reference layer and the free layer. The tunnel barrier is configured to enable electrons to tunnel through the tunnel barrier between the interfacial reference layer and the free layer. A first in-situ alignment is provided between a tunnel barrier lattice structure of the tunnel barrier and an interfacial reference layer lattice structure of the interfacial reference layer. A second in-situ alignment is provided between the tunnel barrier lattice structure of the tunnel barrier and a free layer lattice structure of the free layer. The PMA reference layer lattice structure is not aligned with the interfacial reference layer lattice structure.
    Type: Application
    Filed: December 30, 2014
    Publication date: June 30, 2016
    Inventors: Guohan Hu, Daniel C. Worledge
  • Publication number: 20160163966
    Abstract: Magnetic memory devices having an antiferromagnetic reference layer based on Co and Ir are provided. In one aspect, a magnetic memory device includes a reference magnetic layer having multiple Co-containing layers oriented in a stack, wherein adjacent Co-containing layers in the stack are separated by an Ir-containing layer such that the adjacent Co-containing layers in the stack are anti-parallel coupled by the Ir-containing layer therebetween; and a free magnetic layer separated from the reference magnetic layer by a barrier layer. A method of writing data to a magnetic random access memory device having at least one of the present magnetic memory cells is also provided.
    Type: Application
    Filed: December 5, 2014
    Publication date: June 9, 2016
    Inventors: Guohan Hu, Luqiao Liu, Jonathan Z. Sun, Daniel C. Worledge
  • Publication number: 20160099404
    Abstract: A device includes a seed layer, a magnetic track layer disposed on the seed layer, an alloy layer disposed on the magnetic track layer, a tunnel barrier layer disposed on the alloy layer, a pinning layer disposed on the tunnel barrier layer, a synthetic antiferromagnetic layer spacer disposed on the pinning layer, a pinned layer disposed on the synthetic antiferromagnetic spacer layer and an antiferromagnetic layer disposed on the pinned layer, and another device includes a seed layer, an antiferromagnetic layer disposed on the seed layer, a pinned layer disposed on the antiferromagnetic layer, a synthetic antiferromagnetic layer spacer disposed on the pinned layer, a pinning layer disposed on the synthetic antiferromagnetic layer spacer, a tunnel barrier layer disposed on the pinning layer, an alloy layer disposed on the tunnel barrier layer and a magnetic track layer disposed on alloy layer.
    Type: Application
    Filed: October 6, 2014
    Publication date: April 7, 2016
    Inventors: Guohan Hu, Cheng-Wei Chien
  • Patent number: 9093103
    Abstract: A mechanism is provided for a structure with perpendicular magnetic anisotropy. A bottom oxide layer is disposed, and a magnetic layer is disposed adjacent to the bottom oxide layer. The magnetic layer includes iron and is magnetized perpendicularly to a plane of the magnetic layer. A top oxide layer is disposed adjacent to the magnetic layer.
    Type: Grant
    Filed: July 2, 2013
    Date of Patent: July 28, 2015
    Assignee: International Business Machines Corporation
    Inventors: Guohan Hu, Daniel Worledge
  • Patent number: 9087543
    Abstract: A mechanism is provided for a structure with perpendicular magnetic anisotropy. A bottom oxide layer is disposed, and a magnetic layer is disposed adjacent to the bottom oxide layer. The magnetic layer includes iron and is magnetized perpendicularly to a plane of the magnetic layer. A top oxide layer is disposed adjacent to the magnetic layer.
    Type: Grant
    Filed: June 6, 2013
    Date of Patent: July 21, 2015
    Assignee: International Business Machines Corporation
    Inventors: Guohan Hu, Daniel Worledge
  • Patent number: 9059399
    Abstract: A mechanism is provided for a spin torque transfer random access memory device. A reference layer is disposed on a seed layer. A tunnel barrier is disposed on the reference layer. A free layer is disposed on the tunnel barrier. A cap layer is disposed on the free layer. The free layer includes a magnetic layer and a metal oxide layer, in which the magnetic layer is disposed on the tunnel barrier and the metal oxide layer is disposed on the magnetic layer. A metal material used in the metal oxide layer includes at least one of Ti, Ta, Ru, Hf, Al, La, and any combination thereof.
    Type: Grant
    Filed: June 6, 2013
    Date of Patent: June 16, 2015
    Assignee: International Business Machines Corporation
    Inventor: Guohan Hu
  • Patent number: 9059389
    Abstract: A mechanism is provided for a spin torque transfer random access memory device. A tunnel barrier is disposed on a reference layer, and a free layer is disposed on the tunnel barrier. The free layer includes an iron layer as a top part of the free layer. A metal oxide layer is disposed on the iron layer, and a cap layer is disposed on the metal oxide layer.
    Type: Grant
    Filed: June 6, 2013
    Date of Patent: June 16, 2015
    Assignee: International Business Machines Corporation
    Inventor: Guohan Hu
  • Patent number: 8947915
    Abstract: A thermal spin torque transfer magnetoresistive random access memory (MRAM) apparatus includes a magnetic tunnel junction and a tunnel junction programming circuit. The magnetic tunnel junction includes a reference layer having a fixed magnetic polarity, a tunnel barrier layer, and a free layer on an opposite side of the tunnel barrier layer from the reference layer. The free layer includes a first layer having a first Curie temperature and a second layer having a second Curie temperature different from the first Curie temperature. The tunnel junction programming circuit is configured to apply a current through the magnetic tunnel junction to generate a write temperature in the magnetic tunnel junction and to write to the free layer of the magnetic tunnel junction.
    Type: Grant
    Filed: December 17, 2012
    Date of Patent: February 3, 2015
    Assignee: International Business Machines Corporation
    Inventors: Daniel C. Worledge, Guohan Hu
  • Patent number: 8947917
    Abstract: A thermal spin torque transfer magnetoresistive random access memory (MRAM) apparatus includes a magnetic tunnel junction and a tunnel junction programming circuit. The magnetic tunnel junction includes a reference layer having a fixed magnetic polarity, a tunnel barrier layer, and a free layer on an opposite side of the tunnel barrier layer from the reference layer. The free layer includes a first layer having a first Curie temperature and a second layer having a second Curie temperature different from the first Curie temperature. The tunnel junction programming circuit is configured to apply a current through the magnetic tunnel junction to generate a write temperature in the magnetic tunnel junction and to write to the free layer of the magnetic tunnel junction.
    Type: Grant
    Filed: August 16, 2013
    Date of Patent: February 3, 2015
    Assignee: International Business Machines Corporation
    Inventors: Daniel C. Worledge, Guohan Hu
  • Publication number: 20140363902
    Abstract: A mechanism is provided for a spin torque transfer random access memory device. A reference layer is disposed on a seed layer. A tunnel barrier is disposed on the reference layer. A free layer is disposed on the tunnel barrier. A cap layer is disposed on the free layer. The free layer includes a magnetic layer and a metal oxide layer, in which the magnetic layer is disposed on the tunnel barrier and the metal oxide layer is disposed on the magnetic layer. A metal material used in the metal oxide layer includes at least one of Ti, Ta, Ru, Hf, Al, La, and any combination thereof.
    Type: Application
    Filed: July 2, 2013
    Publication date: December 11, 2014
    Inventor: Guohan Hu
  • Publication number: 20140361389
    Abstract: A mechanism is provided for a spin torque transfer random access memory device. A tunnel barrier is disposed on a reference layer, and a free layer is disposed on the tunnel barrier. The free layer includes an iron layer as a top part of the free layer. A metal oxide layer is disposed on the iron layer, and a cap layer is disposed on the metal oxide layer.
    Type: Application
    Filed: June 6, 2013
    Publication date: December 11, 2014
    Inventor: Guohan Hu
  • Publication number: 20140363569
    Abstract: A mechanism is provided for a structure with perpendicular magnetic anisotropy. A bottom oxide layer is disposed, and a magnetic layer is disposed adjacent to the bottom oxide layer. The magnetic layer includes iron and is magnetized perpendicularly to a plane of the magnetic layer. A top oxide layer is disposed adjacent to the magnetic layer.
    Type: Application
    Filed: July 2, 2013
    Publication date: December 11, 2014
    Inventors: Guohan Hu, Daniel Worledge
  • Publication number: 20140361390
    Abstract: A mechanism is provided for a spin torque transfer random access memory device. A reference layer is disposed on a seed layer. A tunnel barrier is disposed on the reference layer. A free layer is disposed on the tunnel barrier. A cap layer is disposed on the free layer. The free layer includes a magnetic layer and a metal oxide layer, in which the magnetic layer is disposed on the tunnel barrier and the metal oxide layer is disposed on the magnetic layer. A metal material used in the metal oxide layer includes at least one of Ti, Ta, Ru, Hf, Al, La, and any combination thereof.
    Type: Application
    Filed: June 6, 2013
    Publication date: December 11, 2014
    Inventor: Guohan Hu
  • Publication number: 20140363701
    Abstract: A mechanism is provided for a structure with perpendicular magnetic anisotropy. A bottom oxide layer is disposed, and a magnetic layer is disposed adjacent to the bottom oxide layer. The magnetic layer includes iron and is magnetized perpendicularly to a plane of the magnetic layer. A top oxide layer is disposed adjacent to the magnetic layer.
    Type: Application
    Filed: June 6, 2013
    Publication date: December 11, 2014
    Inventors: Guohan Hu, Daniel Worledge
  • Patent number: 8871530
    Abstract: A mechanism is provided for a spin torque transfer random access memory device. A tunnel barrier is disposed on a reference layer, and a free layer is disposed on the tunnel barrier. The free layer includes an iron layer as a top part of the free layer. A metal oxide layer is disposed on the iron layer, and a cap layer is disposed on the metal oxide layer.
    Type: Grant
    Filed: July 2, 2013
    Date of Patent: October 28, 2014
    Assignee: International Business Machines Corporation
    Inventor: Guohan Hu