Patents by Inventor Christian Kaiser

Christian Kaiser 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: 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
  • Patent number: 11430592
    Abstract: A magnetic element includes a first free layer, a barrier layer over the first free layer, and a second free layer over the barrier layer. The first free layer includes a first ferromagnetic bilayer and a first amorphous insertion layer (e.g., CoHf) between the first ferromagnetic bilayer. The first ferromagnetic bilayer is selected from CoB, CoFeB, FeB, and combinations thereof. The second free layer includes a second ferromagnetic bilayer and a second amorphous insertion layer (e.g., CoHf) between the second ferromagnetic bilayer. The second ferromagnetic bilayer is selected from CoB, CoFeB, FeB, and combinations thereof. Each of the first and the second amorphous insertion layer independently can be ferromagnetic or non-ferromagnetic and can have a recrystallization temperature of about 300° C. and above. The magnetic element can further include a non-ferromagnetic amorphous buffer layer and/or a non-ferromagnetic amorphous capping layer.
    Type: Grant
    Filed: February 25, 2021
    Date of Patent: August 30, 2022
    Assignee: Western Digital Technologies, Inc.
    Inventors: Zhitao Diao, Christian Kaiser, Yuankai Zheng
  • Patent number: 11415645
    Abstract: The present disclosure generally relates to a Wheatstone bridge array comprising TMR sensors and a method of fabrication thereof. In the Wheatstone bridge array, there are four distinct TMR sensors. The TMR sensors are all fabricated simultaneously to create four identical TMR sensors that have synthetic antiferromagnetic free layers as the top layer. The synthetic antiferromagnetic free layers comprise a first magnetic layer, a spacer layer, and a second magnetic layer. After forming the four identical TMR sensors, the spacer layer and the second magnetic layer are removed from two TMR sensors. Following the removal of the spacer layer and the second magnetic layer, a new magnetic layer is formed on the now exposed first magnetic layer such that the new magnetic layer has substantially the same thickness as the spacer layer and second magnetic layer combined.
    Type: Grant
    Filed: December 30, 2019
    Date of Patent: August 16, 2022
    Assignee: Western Digital Technologies, Inc.
    Inventors: Yuankai Zheng, Christian Kaiser, Zhitao Diao, Chih-Ching Hu, Chen-jung Chien, Yung-Hung Wang, Ming Mao, Ming Jiang
  • Patent number: 11385305
    Abstract: A tunneling magnetoresistance (TMR) sensor device is disclosed that includes one or more TMR sensors. The TMR sensor device comprises a first resistor comprising a first TMR film, a second resistor comprising a second TMR film different than the first TMR film, a third resistor comprising the second TMR film, and a fourth resistor comprising the first TMR film. The first TMR film comprises a reference layer having a first magnetization direction anti-parallel to a second magnetization direction of a pinned layer. The second TMR film comprises a reference layer having a first magnetization direction parallel to a second magnetization direction of a first pinned layer, and a second pinned layer having a third magnetization direction anti-parallel to the first magnetization direction of the reference layer and the second magnetization direction of the first pinned layer.
    Type: Grant
    Filed: December 18, 2019
    Date of Patent: July 12, 2022
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Yuankai Zheng, Christian Kaiser, Zhitao Diao, Chih-Ching Hu, Chen-Jung Chien, Yung-Hung Wang, Dujiang Wan, Ronghui Zhou, Ming Mao, Ming Jiang, Daniele Mauri
  • Patent number: 11385306
    Abstract: Embodiments of the present disclosure generally relate to a sensor of magnetic tunnel junctions (MTJs) with shape anisotropy. In one embodiment, a tunnel magnetoresistive (TMR) based magnetic sensor in a Wheatstone configuration includes at least one magnetic tunnel junctions (MTJ). The MTJ includes a free layer having a first edge and a second edge. The free layer has a thickness of about 100 ? or more. The free layer has a width and a height with a width-to-height aspect ratio of about 4:1 or more. The MTJ has a first hard bias element positioned proximate the first edge of the free layer and a second hard bias element positioned proximate the second edge of the free layer.
    Type: Grant
    Filed: December 27, 2019
    Date of Patent: July 12, 2022
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Daniele Mauri, Lei Wang, Yuankai Zheng, Christian Kaiser, Chih-Ching Hu, Ming Mao, Ming Jiang, Petrus Antonius Van Der Heijden
  • 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
  • Publication number: 20220093305
    Abstract: A magnetic element includes a first free layer, a barrier layer over the first free layer, and a second free layer over the barrier layer. The first free layer includes a first ferromagnetic bilayer and a first amorphous insertion layer (e.g., CoHf) between the first ferromagnetic bilayer. The first ferromagnetic bilayer is selected from CoB, CoFeB, FeB, and combinations thereof. The second free layer includes a second ferromagnetic bilayer and a second amorphous insertion layer (e.g., CoHf) between the second ferromagnetic bilayer. The second ferromagnetic bilayer is selected from CoB, CoFeB, FeB, and combinations thereof. Each of the first and the second amorphous insertion layer independently can be ferromagnetic or non-ferromagnetic and can have a recrystallization temperature of about 300° C. and above. The magnetic element can further include a non-ferromagnetic amorphous buffer layer and/or a non-ferromagnetic amorphous capping layer.
    Type: Application
    Filed: February 25, 2021
    Publication date: March 24, 2022
    Inventors: Zhitao DIAO, Christian KAISER, Yuankai ZHENG
  • 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
  • Patent number: 11209505
    Abstract: A method of fabricating a TMR based magnetic sensor in a Wheatstone configuration includes conducting a first anneal of a magnetic tunnel junction (MTJ) and conducting a second anneal of the MTJ. The MTJ includes a first antiferromagnetic (AFM) pinning layer, a pinned layer over the first AFM pinning layer, an anti-parallel coupled layer over the pinned layer, a reference layer over the anti-parallel coupled layer, a barrier layer over the reference layer, a free layer over the barrier layer, and a second antiferromagnetic pinning layer over the free layer. The first anneal of the MTJ sets the first AFM pinning layer, the pinned layer, the free layer, and the second AFM pinning layer in a first magnetization direction. The second anneal of the MTJ resets the free layer and the second AFM pinning layer in a second magnetization direction. An operating field range of the TMR based magnetic sensor is over ±100 Oe.
    Type: Grant
    Filed: December 27, 2019
    Date of Patent: December 28, 2021
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Daniele Mauri, Yuankai Zheng, Lei Wang, Christian Kaiser
  • Patent number: 11199594
    Abstract: Embodiments of the present disclosure generally relate to a large field range TMR sensor of magnetic tunnel junctions (MTJs) with a free layer having an intrinsic anisotropy. In one embodiment, a tunnel magnetoresistive (TMR) based magnetic sensor in a Wheatstone configuration includes at least one MTJ. The MTJ includes a free layer having an intrinsic anisotropy produced by deposition at a high oblique angle from normal. Magnetic domain formations within the free layer can be further controlled by a pinned layer canted at an angle to the intrinsic anisotropy of the free layer, by a hard bias element, by shape anisotropy, or combinations thereof.
    Type: Grant
    Filed: December 27, 2019
    Date of Patent: December 14, 2021
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Daniele Mauri, Alexander M. Zeltser, Goncalo Baiao De Albuquerque, Yuankai Zheng, Christian Kaiser
  • Patent number: 11125840
    Abstract: The present disclosure generally relates to a tunnel magnetoresistive (TMR) device. The TMR device includes a high radiation reflective layer between the bottom shield of the TMR device and the magnetic seed layer. The high radiation reflective layer helps to maintain the TMR device temperature during transportation between processing chambers. Additionally, the high radiation reflective layer decreases the resistance area (RA) of the TMR device while also increasing the magnetoresistance (MR) of the TMR device.
    Type: Grant
    Filed: February 18, 2020
    Date of Patent: September 21, 2021
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Yuankai Zheng, Christian Kaiser, Zhitao Diao
  • Publication number: 20210255256
    Abstract: The present disclosure generally relates to a tunnel magnetoresistive (TMR) device. The TMR device includes a high radiation reflective layer between the bottom shield of the TMR device and the magnetic seed layer. The high radiation reflective layer helps to maintain the TMR device temperature during transportation between processing chambers. Additionally, the high radiation reflective layer decreases the resistance area (RA) of the TMR device while also increasing the magnetoresistance (MR) of the TMR device.
    Type: Application
    Filed: February 18, 2020
    Publication date: August 19, 2021
    Inventors: Yuankai ZHENG, Christian KAISER, Zhitao DIAO
  • Patent number: 11014878
    Abstract: The present invention relates to a method for preparing 3-methylthiopropionaldehyde by reacting methyl mercaptan with acrolein, in which deviations in the stoichiometry of methyl mercaptan to acrolein in the reaction to give 3-methylthiopropionaldehyde are compensated for by supplying or by forming 1,3-bis(methylthio)-1-propanol, and also to the use of 1,3-bis(methylthio)-1-propanol as a storage form of methyl mercaptan and/or 3-methylthiopropionaldehyde.
    Type: Grant
    Filed: February 14, 2017
    Date of Patent: May 25, 2021
    Assignee: Evonik Operations GmbH
    Inventors: Stephan Rautenberg, Sascha Ceylan, Martin Koerfer, Judith Hierold, Harald Jakob, Christian Kaiser, Rainer Malzkorn, Thorsten Merker, Anja Nordschild
  • Publication number: 20210063505
    Abstract: A method of fabricating a TMR based magnetic sensor in a Wheatstone configuration includes conducting a first anneal of a magnetic tunnel junction (MTJ) and conducting a second anneal of the MTJ. The MTJ includes a first antiferromagnetic (AFM) pinning layer, a pinned layer over the first AFM pinning layer, an anti-parallel coupled layer over the pinned layer, a reference layer over the anti-parallel coupled layer, a barrier layer over the reference layer, a free layer over the barrier layer, and a second antiferromagnetic pinning layer over the free layer. The first anneal of the MTJ sets the first AFM pinning layer, the pinned layer, the free layer, and the second AFM pinning layer in a first magnetization direction. The second anneal of the MTJ resets the free layer and the second AFM pinning layer in a second magnetization direction. An operating field range of the TMR based magnetic sensor is over ±100 Oe.
    Type: Application
    Filed: December 27, 2019
    Publication date: March 4, 2021
    Inventors: Daniele MAURI, Yuankai ZHENG, Lei WANG, Christian KAISER
  • Publication number: 20210063500
    Abstract: Embodiments of the present disclosure generally relate to a large field range TMR sensor of magnetic tunnel junctions (MTJs) with a free layer having an intrinsic anisotropy. In one embodiment, a tunnel magnetoresistive (TMR) based magnetic sensor in a Wheatstone configuration includes at least one MTJ. The MTJ includes a free layer having an intrinsic anisotropy produced by deposition at a high oblique angle from normal. Magnetic domain formations within the free layer can be further controlled by a pinned layer canted at an angle to the intrinsic anisotropy of the free layer, by a hard bias element, by shape anisotropy, or combinations thereof.
    Type: Application
    Filed: December 27, 2019
    Publication date: March 4, 2021
    Inventors: Daniele MAURI, Alexander M. ZELTSER, Goncalo BAIAO DE ALBUQUERQUE, Yuankai ZHENG, Christian KAISER
  • Publication number: 20210063507
    Abstract: The present disclosure generally relates to a Wheatstone bridge array that has four resistors. Each resistor includes a plurality of TMR structures. Two resistors have identical TMR structures. The remaining two resistors also have identical TMR structures, though the TMR structures are different from the other two resistors. Additionally, the two resistors that have identical TMR structures have a different resistance area as compared to the remaining two resistors that have identical TMR structures. Therefore, the working bias field for the Wheatstone bridge array is non-zero.
    Type: Application
    Filed: December 30, 2019
    Publication date: March 4, 2021
    Inventors: Yuankai ZHENG, Christian KAISER, Zhitao DIAO, Chih-Ching HU, Chen-jung CHIEN, Yung-Hung WANG, Dujiang WAN, Ronghui ZHOU, Ming MAO, Ming JIANG, Daniele MAURI
  • Publication number: 20210063504
    Abstract: A tunneling magnetoresistance (TMR) sensor device is disclosed that includes one or more TMR sensors. The TMR sensor device comprises a first resistor comprising a first TMR film, a second resistor comprising a second TMR film different than the first TMR film, a third resistor comprising the second TMR film, and a fourth resistor comprising the first TMR film. The first TMR film comprises a reference layer having a first magnetization direction anti-parallel to a second magnetization direction of a pinned layer. The second TMR film comprises a reference layer having a first magnetization direction parallel to a second magnetization direction of a first pinned layer, and a second pinned layer having a third magnetization direction anti-parallel to the first magnetization direction of the reference layer and the second magnetization direction of the first pinned layer.
    Type: Application
    Filed: December 18, 2019
    Publication date: March 4, 2021
    Inventors: Yuankai ZHENG, Christian KAISER, Zhitao DIAO, Chih-Ching HU, Chen-Jung CHIEN, Yung-Hung WANG, Dujiang WAN, Ronghui ZHOU, Ming MAO, Ming JIANG, Daniele MAURI
  • Patent number: D917232
    Type: Grant
    Filed: September 21, 2018
    Date of Patent: April 27, 2021
    Inventor: Mark Christian Kaiser
  • Patent number: D917233
    Type: Grant
    Filed: September 25, 2018
    Date of Patent: April 27, 2021
    Inventor: Mark Christian Kaiser
  • Patent number: D925986
    Type: Grant
    Filed: September 12, 2018
    Date of Patent: July 27, 2021
    Inventor: Mark Christian Kaiser