Patents by Inventor James Mac Freitag

James Mac Freitag 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: 11881236
    Abstract: The present disclosure generally relates to a magnetic recording head comprising a spintronic device. The spintronic device is disposed between a main pole and a trailing shield of the magnetic recording head. The spintronic device comprises a multilayer spacer layer comprising a Cu layer in contact with a spin torque layer and a spin transparent texture layer disposed on the Cu layer, the spin transparent texture layer comprising AgSn or AgZn. A multilayer notch comprising a CoFe layer is disposed over the spin transparent texture layer of the multilayer spacer layer and a Heusler alloy layer is disposed on the CoFe layer, the Heusler alloy layer comprising CoMnGe, CoFeGe, or CoFeMnGe. The multilayer spacer layer and the multilayer notch result in the spintronic device having a high spin polarization and a reduced critical current.
    Type: Grant
    Filed: June 21, 2022
    Date of Patent: January 23, 2024
    Assignee: Western Digital Technologies, Inc.
    Inventors: James Mac Freitag, Susumu Okamura, Christian Kaiser
  • Patent number: 11862205
    Abstract: The present disclosure generally relates to a magnetic recording device having a magnetic recording head comprising a spintronic device. The spintronic device is disposed between a main pole and a trailing shield at a media facing surface. The spintronic device comprises a spin torque layer (STL) and a multilayer seed layer disposed in contact with the STL. The spintronic device may further comprise a field generation layer disposed between the trailing shield and the STL. The multilayer seed layer comprises an optional high etch rate layer, a heat dissipation layer comprising Ru disposed in contact with the optional high etch rate layer, and a cooling layer comprising Cr disposed in contact with the heat dissipation layer and the main pole. The high etch rate layer comprises Cu and has a high etch rate to improve the shape of the spintronic device during the manufacturing process.
    Type: Grant
    Filed: June 21, 2022
    Date of Patent: January 2, 2024
    Assignee: Western Digital Technologies, Inc.
    Inventors: James Mac Freitag, Yongchul Ahn, Susumu Okamura, Christian Kaiser
  • Publication number: 20230410841
    Abstract: The present disclosure generally relates to a magnetic recording head comprising a spintronic device. The spintronic device is disposed between a main pole and a trailing shield of the magnetic recording head. The spintronic device comprises a multilayer spacer layer comprising a Cu layer in contact with a spin torque layer and a spin transparent texture layer disposed on the Cu layer, the spin transparent texture layer comprising AgSn or AgZn. A multilayer notch comprising a CoFe layer is disposed over the spin transparent texture layer of the multilayer spacer layer and a Heusler alloy layer is disposed on the CoFe layer, the Heusler alloy layer comprising CoMnGe, CoFeGe, or CoFeMnGe. The multilayer spacer layer and the multilayer notch result in the spintronic device having a high spin polarization and a reduced critical current.
    Type: Application
    Filed: June 21, 2022
    Publication date: December 21, 2023
    Applicant: Western Digital Technologies, Inc.
    Inventors: James Mac FREITAG, Susumu OKAMURA, Christian KAISER
  • Publication number: 20230410840
    Abstract: The present disclosure generally relates to a magnetic recording device having a magnetic recording head comprising a spintronic device. The spintronic device is disposed between a main pole and a trailing shield at a media facing surface. The spintronic device comprises a spin torque layer (STL) and a multilayer seed layer disposed in contact with the STL. The spintronic device may further comprise a field generation layer disposed between the trailing shield and the STL. The multilayer seed layer comprises an optional high etch rate layer, a heat dissipation layer comprising Ru disposed in contact with the optional high etch rate layer, and a cooling layer comprising Cr disposed in contact with the heat dissipation layer and the main pole. The high etch rate layer comprises Cu and has a high etch rate to improve the shape of the spintronic device during the manufacturing process.
    Type: Application
    Filed: June 21, 2022
    Publication date: December 21, 2023
    Applicant: Western Digital Technologies, Inc.
    Inventors: James Mac FREITAG, Yongchul AHN, Susumu OKAMURA, Christian KAISER
  • Patent number: 11683993
    Abstract: Aspects of the present disclosure generally relate to a spintronic device for use in a magnetic media drive, a magnetoresistive random access memory device, a magnetic sensor, or a magnetic recording write head. The spintronic device comprises a multilayer structure having a negative anisotropic field and a negative spin polarization. The multilayer structure comprises a plurality of layers, each layer of the plurality of layers comprising a first sublayer comprising Fe and a second sublayer comprising Co. At least one of the first sublayer and the second sublayer comprises one or more of Cr, V, and Ti. The first and second sublayers are alternating. The negative anisotropic field of the multilayer structure is between about ?0.5 T to about ?0.8 T, and an effective magnetization of the multilayer structure is between about 2.4 T to about 2.8 T.
    Type: Grant
    Filed: March 23, 2021
    Date of Patent: June 20, 2023
    Assignee: Western Digital Technologies, Inc.
    Inventors: Susumu Okamura, Christian Kaiser, James Mac Freitag
  • Patent number: 11682420
    Abstract: Certain embodiments are directed to a spin torque oscillator (STO) device in a microwave assisted magnetic recording (MAMR) device. The magnetic recording head includes a seed layer, a spin polarization layer over the seed layer, a spacer layer over the spin polarization layer, and a field generation layer is over the spacer layer. In one embodiment, the seed layer comprises a tantalum alloy layer. In another embodiment, the seed layer comprises a template layer and a damping reduction layer over the template layer. In yet another embodiment, the seed layer comprises a texture reset layer, a template layer on the texture reset layer, and a damping reduction layer on the template layer.
    Type: Grant
    Filed: August 31, 2021
    Date of Patent: June 20, 2023
    Assignee: Western Digital Technologies, Inc.
    Inventors: James Mac Freitag, Zheng Gao, Susumu Okamura, Brian R. York
  • Patent number: 11657836
    Abstract: Aspects of the present disclosure generally relate to a magnetic recording head of a spintronic device, such as a write head of a data storage device, for example a magnetic media drive. In one example, a magnetic recording head includes a main pole, a trailing shield, and a spin torque layer (STL) between the main pole and the trailing shield. The magnetic recording head includes a first layer structure on the main pole, and the first layer structure includes a negative polarization layer. The magnetic recording head also includes a second layer structure disposed on the negative polarization layer and between the negative polarization layer and the STL. The negative polarization layer is an FeCr layer. The second layer structure includes a Cr layer disposed on the FeCr layer, and a Cu layer disposed on the Cr layer and between the Cr layer and the STL.
    Type: Grant
    Filed: January 28, 2022
    Date of Patent: May 23, 2023
    Assignee: Western Digital Technologies, Inc.
    Inventors: James Mac Freitag, Susumu Okamura, Alexander Goncharov, Zheng Gao
  • Patent number: 11646052
    Abstract: A magnetic recording write head and system has a spin-torque oscillator (STO) located between the write head's write pole and trailing shield. The STO's ferromagnetic free layer is located near the write pole with a multilayer seed layer between the write pole and the free layer. The STO's nonmagnetic spacer layer is between the free layer and the STO's ferromagnetic polarizer. The polarizer may be the trailing shield of the write head, one or more separate polarizer layers, or combinations thereof. The STO electrical circuitry causes electron flow from the write pole to the trailing shield. The multilayer seed layer removes the spin polarization of electrons from the write pole, which enables electrons reflected from the polarizer layer to become spin polarized, which creates the spin transfer torque on the magnetization of the free layer. The multilayer seed layer includes a Mn or a Mn-alloy layer.
    Type: Grant
    Filed: April 12, 2021
    Date of Patent: May 9, 2023
    Assignee: Western Digital Technologies, Inc.
    Inventors: James Mac Freitag, Zheng Gao, Masahiko Hashimoto, Sangmun Oh
  • Publication number: 20230030248
    Abstract: Embodiments of the present disclosure generally relate to spintronic devices, and more specifically to self-cooling spintronic devices. In an embodiment, a device is provided. The device includes a spintronic device having a first side and a second side opposite the first side, a first layer disposed on the first side, and a second layer disposed on the second side, the first layer having a Seebeck coefficient that is different from a Seebeck coefficient of the second layer.
    Type: Application
    Filed: July 28, 2021
    Publication date: February 2, 2023
    Inventors: Susumu OKAMURA, Christian KAISER, Xinjiang SHEN, Yongchul AHN, James Mac FREITAG
  • Publication number: 20220310900
    Abstract: Aspects of the present disclosure generally relate to a spintronic device for use in a magnetic media drive, a magnetoresistive random access memory device, a magnetic sensor, or a magnetic recording write head. The spintronic device comprises a multilayer structure having a negative anisotropic field and a negative spin polarization. The multilayer structure comprises a plurality of layers, each layer of the plurality of layers comprising a first sublayer comprising Fe and a second sublayer comprising Co. At least one of the first sublayer and the second sublayer comprises one or more of Cr, V, and Ti. The first and second sublayers are alternating. The negative anisotropic field of the multilayer structure is between about ?0.5 T to about ?0.8 T, and an effective magnetization of the multilayer structure is between about 2.4 T to about 2.8 T.
    Type: Application
    Filed: March 23, 2021
    Publication date: September 29, 2022
    Inventors: Susumu OKAMURA, Christian KAISER, James Mac FREITAG
  • Publication number: 20220148619
    Abstract: Aspects of the present disclosure generally relate to a magnetic recording head of a spintronic device, such as a write head of a data storage device, for example a magnetic media drive. In one example, a magnetic recording head includes a main pole, a trailing shield, and a spin torque layer (STL) between the main pole and the trailing shield. The magnetic recording head a first layer structure on the main pole, and the first layer structure includes a negative polarization layer. The magnetic recording head also includes a second layer structure disposed on the negative polarization layer and between the negative polarization layer and the STL. The negative polarization layer is an FeCr layer. The second layer structure includes a Cr layer disposed on the FeCr layer, and a Cu layer disposed on the Cr layer and between the Cr layer and the STL.
    Type: Application
    Filed: January 28, 2022
    Publication date: May 12, 2022
    Applicant: Western Digital Technologies, Inc.
    Inventors: James Mac FREITAG, Susumu OKAMURA, Alexander GONCHAROV, Zheng GAO
  • Patent number: 11289118
    Abstract: Aspects of the present disclosure generally relate to a magnetic recording head of a magnetic media drive. In one example, a magnetic recording head includes a main pole, a trailing shield, and spintronic device disposed between the main pole and the trailing shield. The spintronic device comprises a negative polarization layer (NPL) disposed on the main pole, the NPL comprising FeTi, FeV, FeCr, or FeN, an interface layer disposed on the NPL, the interface layer comprising V, Cr, or Ru, a spacer layer disposed on the interface layer, and a spin torque layer (FGL) disposed on the spacer layer. When current is applied to the spintronic device, the NPL and a first interface disposed between the NPL and the interface layer have a negative spin polarization while the FGL and a second interface disposed between the FGL and the spacer layer have a positive spin polarization.
    Type: Grant
    Filed: February 24, 2021
    Date of Patent: March 29, 2022
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Christian Kaiser, Andrew Chen, Zheng Gao, Susumu Okamura, James Mac Freitag
  • Patent number: 11283006
    Abstract: The present disclosure generally relates to magnetoresistive device apparatus and methods. The magnetoresistive device includes a read head. The read head is a tunneling magnetoresistive reader that includes a multilayer free layer structure. The multilayer structure includes one or more layers of Co or FCC FeCo sandwiched between a BCC CoFe50 nanolayer and an amorphous CoFeB layer. The one or more layers of Co or FCC FeCo create nanocrystalline disorder that allows the thickness of the amorphous CoFeB layer to be reduced while retaining or even improving TMR and reducing the interlayer coupling field.
    Type: Grant
    Filed: May 5, 2020
    Date of Patent: March 22, 2022
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: James Mac Freitag, Zheng Gao
  • Patent number: 11257514
    Abstract: Aspects of the present disclosure generally relate to a magnetic recording head of a spintronic device, such as a write head of a data storage device, for example a magnetic media drive. In one example, a magnetic recording head includes a main pole, a trailing shield, and a spin torque layer (STL) between the main pole and the trailing shield. The magnetic recording head includes a first layer structure on the main pole, and the first layer structure includes a negative polarization layer. The magnetic recording head also includes a second layer structure disposed on the negative polarization layer and between the negative polarization layer and the STL. The negative polarization layer is an FeCr layer. The second layer structure includes a Cr layer disposed on the FeCr layer, and a Cu layer disposed on the Cr layer and between the Cr layer and the STL.
    Type: Grant
    Filed: June 25, 2020
    Date of Patent: February 22, 2022
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: James Mac Freitag, Susumu Okamura, Alexander Goncharov, Zheng Gao
  • Publication number: 20210407534
    Abstract: Aspects of the present disclosure generally relate to a magnetic recording head of a spintronic device, such as a write head of a data storage device, for example a magnetic media drive. In one example, a magnetic recording head includes a main pole, a trailing shield, and a spin torque layer (STL) between the main pole and the trailing shield. The magnetic recording head a first layer structure on the main pole, and the first layer structure includes a negative polarization layer. The magnetic recording head also includes a second layer structure disposed on the negative polarization layer and between the negative polarization layer and the STL. The negative polarization layer is an FeCr layer. The second layer structure includes a Cr layer disposed on the FeCr layer, and a Cu layer disposed on the Cr layer and between the Cr layer and the STL.
    Type: Application
    Filed: June 25, 2020
    Publication date: December 30, 2021
    Inventors: James Mac FREITAG, Susumu OKAMURA, Alexander GONCHAROV, Zheng GAO
  • Patent number: 11211083
    Abstract: Embodiments of the present disclosure generally relate to a write head for a magnetic recording device. The write head includes a spin torque oscillator (STO) that has a seed layer formed on a write pole, a spin polarization layer (SPL) formed on the seed layer, a first spacer layer formed on the SPL, a field generation layer (FGL) formed on the first spacer layer, a second spacer layer formed on the FGL, and a notch formed on the second spacer layer. The FGL and the notch are antiferromagnetically coupled through the second spacer layer and thus increases the FGL angle and improves the write capabilities of the write head.
    Type: Grant
    Filed: June 24, 2020
    Date of Patent: December 28, 2021
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Yuankai Zheng, Zheng Gao, Christian Kaiser, Zhitao Diao, Susumu Okamura, James Mac Freitag, Alexander Goncharov
  • Publication number: 20210390977
    Abstract: Certain embodiments are directed to a spin torque oscillator (STO) device in a microwave assisted magnetic recording (MAMR) device. The magnetic recording head includes a seed layer, a spin polarization layer over the seed layer, a spacer layer over the spin polarization layer, and a field generation layer is over the spacer layer. In one embodiment, the seed layer comprises a tantalum alloy layer. In another embodiment, the seed layer comprises a template layer and a damping reduction layer over the template layer. In yet another embodiment, the seed layer comprises a texture reset layer, a template layer on the texture reset layer, and a damping reduction layer on the template layer.
    Type: Application
    Filed: August 31, 2021
    Publication date: December 16, 2021
    Applicant: Western Digital Technologies, Inc.
    Inventors: James Mac FREITAG, Zheng GAO, Susumu OKAMURA, Brian R. YORK
  • Patent number: 11127420
    Abstract: Certain embodiments are directed to a spin torque oscillator (STO) device in a microwave assisted magnetic recording (MAMR) device. The magnetic recording head includes a seed layer, a spin polarization layer over the seed layer, a spacer layer over the spin polarization layer, and a field generation layer is over the spacer layer. In one embodiment, the seed layer comprises a tantalum alloy layer. In another embodiment, the seed layer comprises a template layer and a damping reduction layer over the template layer. In yet another embodiment, the seed layer comprises a texture reset layer, a template layer on the texture reset layer, and a damping reduction layer on the template layer.
    Type: Grant
    Filed: June 24, 2019
    Date of Patent: September 21, 2021
    Assignee: Western Digital Technologies, Inc.
    Inventors: James Mac Freitag, Zheng Gao, Susumu Okamura, Brian York
  • Publication number: 20210233560
    Abstract: A magnetic recording write head and system has a spin-torque oscillator (STO) located between the write head's write pole and trailing shield. The STO's ferromagnetic free layer is located near the write pole with a multilayer seed layer between the write pole and the free layer. The STO's nonmagnetic spacer layer is between the free layer and the STO's ferromagnetic polarizer. The polarizer may be the trailing shield of the write head, one or more separate polarizer layers, or combinations thereof. The STO electrical circuitry causes electron flow from the write pole to the trailing shield. The multilayer seed layer removes the spin polarization of electrons from the write pole, which enables electrons reflected from the polarizer layer to become spin polarized, which creates the spin transfer torque on the magnetization of the free layer. The multilayer seed layer includes a Mn or a Mn-alloy layer.
    Type: Application
    Filed: April 12, 2021
    Publication date: July 29, 2021
    Applicant: Western Digital Technologies, Inc.
    Inventors: James Mac FREITAG, Zheng GAO, Masahiko HASHIMOTO, Sangmun OH
  • Patent number: 10997993
    Abstract: A magnetic recording write head and system has a spin-torque oscillator (STO) located between the write head's write pole and trailing shield. The STO's ferromagnetic free layer is located near the write pole with a multilayer seed layer between the write pole and the free layer. The STO's nonmagnetic spacer layer is between the free layer and the STO's ferromagnetic polarizer. The polarizer may be the trailing shield of the write head, one or more separate polarizer layers, or combinations thereof. The STO electrical circuitry causes electron flow from the write pole to the trailing shield. The multilayer seed layer removes the spin polarization of electrons from the write pole, which enables electrons reflected from the polarizer layer to become spin polarized, which creates the spin transfer torque on the magnetization of the free layer. The multilayer seed layer includes a Mn or a Mn-alloy layer.
    Type: Grant
    Filed: February 14, 2020
    Date of Patent: May 4, 2021
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: James Mac Freitag, Zheng Gao, Masahiko Hashimoto, Sangmun Oh