Patents by Inventor Kuok San Ho

Kuok San Ho 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: 10861485
    Abstract: Embodiments of the present disclosure generally relate to data storage devices, and more specifically, to storage devices employing an energy-assisted magnetic recording write head. The write head may comprise a main pole, a trailing shield, a conducting gap disposed between the main pole and the trailing shield, and one or more current blockers. The conducting gap may be conformal with the main pole. The one or more current blockers may be configured to direct the current from the main pole to the trailing shield through the conducting gap. The one or more current blockers may be further configured to recess the conducting gap away from the media facing surface. The one or more current blockers may be configured to direct the current away from a media facing surface of the write head.
    Type: Grant
    Filed: August 17, 2020
    Date of Patent: December 8, 2020
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Muhammad Asif Bashir, Yaguang Wei, Petrus Antonius Van Der Heijden, Xinjiang Shen, Terence Lam, Zhigang Bai, Youfeng Zheng, Changqing Shi, Michael Kuok San Ho, Jian-Gang Zhu, Lijie Guan, Venkatesh Chembrolu
  • Publication number: 20200381011
    Abstract: Embodiments of the present disclosure generally relate to data storage devices, and more specifically, to storage devices employing an energy-assisted magnetic recording write head. The write head may comprise a main pole, a trailing shield, a conducting gap disposed between the main pole and the trailing shield, and one or more current blockers. The conducting gap may be conformal with the main pole. The one or more current blockers may be configured to direct the current from the main pole to the trailing shield through the conducting gap. The one or more current blockers may be further configured to recess the conducting gap away from the media facing surface. The one or more current blockers may be configured to direct the current away from a media facing surface of the write head.
    Type: Application
    Filed: August 17, 2020
    Publication date: December 3, 2020
    Inventors: Muhammad ASIF BASHIR, Yaguang WEI, Petrus Antonius VAN DER HEIJDEN, Xinjiang SHEN, Terence LAM, Zhigang BAI, Youfeng ZHENG, Changqing SHI, Michael Kuok San HO, Jian-Gang ZHU, Lijie GUAN, Venkatesh CHEMBROLU
  • Patent number: 10839828
    Abstract: The present disclosure generally relates to data storage devices, and more specifically, to a magnetic media drive employing a magnetic recording head. The head includes a trailing shield, a main pole, side shields surrounding at least a portion of the main pole, and a structure disposed between the trailing shield and the main pole. The structure includes one or more layers and a seed layer. The seed layer is connected to one or more electrical leads to provide an electrical path from the leads to the one or more layers during operation. The seed layer guides the electrical current to the one or more layers and improves heat dissipation of the one or more layers, leading to a reduction in hot spots formed in the one or more layers.
    Type: Grant
    Filed: February 15, 2019
    Date of Patent: November 17, 2020
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Quang Le, Hongquan Jiang, Michael Kuok San Ho
  • Patent number: 10839831
    Abstract: The present disclosure generally relates to a magnetic media drive employing a magnetic recording head. The magnetic recording head comprises a first write head and a second write head. The first write head comprises a first main pole, a first yoke having a first length, and a first coil wrapped around the first yoke. The second write head comprises a second main pole, a second yoke having a second length, a second coil wrapped around the second yoke, and a side shield surrounding two or more surfaces of the second main pole. The side shield comprises a heavy metal layer and a magnetic layer. The second write head comprises an energy-assisted magnetic recording element or stack. The second write head comprises a non-magnetic conductive structure to enable maximum current efficiency and uniformity. A write of the first write head is wider than that of the second write head.
    Type: Grant
    Filed: December 30, 2019
    Date of Patent: November 17, 2020
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Thao A. Nguyen, Michael Kuok San Ho, Zhigang Bai, Zhanjie Li, Quang Le
  • Publication number: 20200349968
    Abstract: The present disclosure generally relates to a magnetic media drive employing a magnetic recording head. The head includes a main pole at a media facing surface (MFS), a trailing shield at the MFS, and a MAMR stack disposed between the main pole and the trailing shield at the MFS. The MAMR stack includes a seed layer and at least one magnetic layer. The seed layer is fabricated from a thermally conductive material having electrical resistivity lower than that of the main pole. The seed layer has a stripe height greater than a stripe height of the at least one magnetic layer. With the extended seed layer, the bias current from the trailing shield to the main pole spreads further away from the MFS along the extended seed layer before flowing into the main pole, reducing temperature rise at or near the MAMR stack, leading to improved write head reliability.
    Type: Application
    Filed: July 17, 2020
    Publication date: November 5, 2020
    Inventors: Michael Kuok San HO, Yunfei DING, Zhigang BAI, Yaguang WEI, Terence LAM, Goncalo Marcos BAIÃO DE ALBUQUERQUE, Xinjiang SHEN, Feng Q. LIU
  • Publication number: 20200349969
    Abstract: Disclosed herein is a data storage device comprising a recording media, a slider comprising a write head having a write-field enhancement structure for recording data to the recording media, an electronics module, and a plurality of lines disposed between and coupled to the slider and the electronics module, wherein at least one line of the plurality of lines is configured to both couple a bias voltage to a body of the slider, and carry a bias current for the write-field enhancement structure. Also disclosed herein is a data storage device comprising a slider with an embedded contact sensor, an electronics module, and a plurality of lines disposed between and coupled to the slider and the electronics module, wherein at least one line of the plurality of lines is configured to both couple a bias voltage to a body of the slider, and provide a signal to the embedded contact sensor.
    Type: Application
    Filed: March 30, 2020
    Publication date: November 5, 2020
    Applicant: Western Digital Technologies, Inc.
    Inventors: John CONTRERAS, Yunfei DING, Kuok San HO, Ian Robson MCFADYEN, Joey Martin POSS
  • Publication number: 20200349967
    Abstract: Disclosed herein are magnetic recording devices and methods of using them. A magnetic recording device comprises a main pole extending to an air-bearing surface (ABS), a trailing shield extending to the ABS, a write-field-enhancing structure disposed between and coupled to the main pole and the trailing shield at the ABS, a write coil configured to magnetize the main pole, a write current control circuit coupled to the write coil and configured to apply a write current to the write coil, wherein the write current comprises a write pulse, and a bias current control circuit coupled to the write-field-enhancing structure and configured to apply a bias current to the write-field-enhancing structure, wherein the bias current comprises a driving pulse offset in time from the write pulse by a delay, wherein the delay substantially coincides with an expected magnetization switch-time lag of a free layer of the write-field-enhancing structure.
    Type: Application
    Filed: March 29, 2020
    Publication date: November 5, 2020
    Applicant: Western Digital Technologies, Inc.
    Inventors: Gonçalo Marcos Baião DE ALBUQUERQUE, Yunfei DING, Alexander GONCHAROV, Kuok San HO, Daniele MAURI, Goran MIHAJLOVIC, Suping SONG, Petrus Antonius VAN DER HEIJDEN
  • Publication number: 20200327899
    Abstract: The present disclosure generally relates to data storage devices, and more specifically, to a magnetic media drive employing a magnetic recording head. The head includes a main pole at a media facing surface (MFS), a trailing shield at the MFS, and a heavy metal layer disposed between the main pole and the trailing shield at the MFS. Spin-orbit torque (SOT) is generated from the heavy metal layer and transferred to a surface of the main pole as a current passes through the heavy metal layer in a cross-track direction. The SOT executes a torque on the surface magnetization of the main pole, which reduces the magnetic flux shunting from the main pole to the trailing shield. With the reduced magnetic flux shunting from the main pole to the trailing shield, write-ability is improved.
    Type: Application
    Filed: June 25, 2020
    Publication date: October 15, 2020
    Inventors: Suping SONG, Zhanjie LI, Michael Kuok San HO, Quang LE, Alexander M. ZELTSER
  • Publication number: 20200327900
    Abstract: A magnetic recording write head has an electrically-conductive structure in the write gap between the write pole and the trailing shield and electrical circuitry for directing current through the write gap. The current through the electrically-conductive structure generates a circular Ampere field which, at the disk-facing end of the write pole, is substantially parallel to the disk-facing end of the write pole. The electrically-conductive structure in the write gap may be a STO or an electrically-conductive layer that is not part of a STO. The current direction through the electrically-conductive structure in the write gap is selected so that the generated Ampere field at the write pole end is in substantially the same direction as the magnetization direction of the write head side shields, which has been discovered to result in minimization of cross-track interference.
    Type: Application
    Filed: June 24, 2020
    Publication date: October 15, 2020
    Inventors: Zhigang BAI, Alexander TARATORIN, Anna ZHENG, Venkatesh CHEMBROLU, Supradeep NARAYANA, Suping SONG, Yaguang WEI, Terence LAM, Michael Kuok San HO, Changqing SHI, Lijie GUAN
  • Patent number: 10796717
    Abstract: A perpendicular magnetic recording write head includes a heater on one side of the pole tip of the main pole and a heat sink on the opposite side of the pole tip. The heater is formed of high resistivity material and is connected to a power source. During writing, power is applied to the heater, which causes a relatively large temperature gradient across the pole tip from the heater to the heat sink. The temperature gradient increases the damping of the ferromagnetic material of the main pole during writing, which increases the switching speed of the main pole.
    Type: Grant
    Filed: July 10, 2020
    Date of Patent: October 6, 2020
    Assignee: Western Digital Technologies, Inc.
    Inventors: Suping Song, Zhanjie Li, Kuok San Ho
  • Patent number: 10789975
    Abstract: A perpendicular magnetic recording write head includes a heater on one side of the pole tip of the main pole and a heat sink on the opposite side of the pole tip. The heater is formed of high resistivity material and is connected to a power source. During writing, power is applied to the heater, which causes a relatively large temperature gradient across the pole tip from the heater to the heat sink. The temperature gradient increases the damping of the ferromagnetic material of the main pole during writing, which increases the switching speed of the main pole.
    Type: Grant
    Filed: November 30, 2018
    Date of Patent: September 29, 2020
    Assignee: Western Digital Technologies, Inc.
    Inventors: Suping Song, Zhanjie Li, Kuok San Ho
  • Patent number: 10777219
    Abstract: Embodiments of the present disclosure generally relate to data storage devices, and more specifically, to storage devices employing an energy-assisted magnetic recording write head. The write head may comprise a main pole, a trailing shield, a conducting gap disposed between the main pole and the trailing shield, and one or more current blockers. The conducting gap may be conformal with the main pole. The one or more current blockers may be configured to direct the current from the main pole to the trailing shield through the conducting gap. The one or more current blockers may be further configured to recess the conducting gap away from the media facing surface. The one or more current blockers may be configured to direct the current away from a media facing surface of the write head.
    Type: Grant
    Filed: June 24, 2019
    Date of Patent: September 15, 2020
    Assignee: Western Digital Technologies, Inc.
    Inventors: Muhammad Asif Bashir, Yaguang Wei, Petrus Antonius Van Der Heijden, Xinjiang Shen, Terence Lam, Zhigang Bai, Youfeng Zheng, Changqing Shi, Michael Kuok San Ho, Jian-Gang Zhu, Lijie Guan, Venkatesh Chembrolu
  • Patent number: 10762919
    Abstract: A perpendicular magnetic recording write head includes a main portion formed of conventional high-moment magnetic materials, and a beveled or tapered trailing portion formed of a Co/Fe multilayer with negative magnetic anisotropy (negative anisotropy constant or —Ku). The Co/Fe multilayer tapered trailing portion has a high saturation magnetization (Ms) and thus functions as part of the write pole to direct the flux perpendicularly to the recording layer. Also, the —Ku Co/Fe multilayer tapered trailing portion has its hard axis oriented substantially orthogonal to the layer thickness and thus substantially prevents flux leakage into the write gap. The —Ku Co/Fe multilayer may also be formed on the sides of the write pole in the cross-track direction to prevent flux leakage into the side gaps.
    Type: Grant
    Filed: January 30, 2018
    Date of Patent: September 1, 2020
    Assignee: Western Digital Technologies, Inc.
    Inventors: Suping Song, Zhanjie Li, Yaguang Wei, Terence Tin-Lok Lam, Kuok San Ho
  • Patent number: 10741202
    Abstract: The present disclosure generally relates to a magnetic media drive employing a magnetic recording head. The head includes a main pole at a media facing surface (MFS), a trailing shield at the MFS, and a MAMR stack disposed between the main pole and the trailing shield at the MFS. The MAMR stack includes a seed layer and at least one magnetic layer. The seed layer is fabricated from a thermally conductive material having electrical resistivity lower than that of the main pole. The seed layer has a stripe height greater than a stripe height of the at least one magnetic layer. With the extended seed layer, the bias current from the trailing shield to the main pole spreads further away from the MFS along the extended seed layer before flowing into the main pole, reducing temperature rise at or near the MAMR stack, leading to improved write head reliability.
    Type: Grant
    Filed: February 14, 2019
    Date of Patent: August 11, 2020
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Michael Kuok San Ho, Yunfei Ding, Zhigang Bai, Yaguang Wei, Terence Lam, Goncalo Baiao de Albuquerque, Xinjiang Shen, Feng Q. Liu
  • Patent number: 10734014
    Abstract: The present disclosure generally relates to data storage devices, and more specifically, to a magnetic media drive employing a magnetic recording head. The head includes a main pole at a media facing surface (MFS), a trailing shield at the MFS, and a heavy metal layer disposed between the main pole and the trailing shield at the MFS. Spin-orbit torque (SOT) is generated from the heavy metal layer and transferred to a surface of the main pole as a current passes through the heavy metal layer in a cross-track direction. The SOT executes a torque on the surface magnetization of the main pole, which reduces the magnetic flux shunting from the main pole to the trailing shield. With the reduced magnetic flux shunting from the main pole to the trailing shield, write-ability is improved.
    Type: Grant
    Filed: June 14, 2018
    Date of Patent: August 4, 2020
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Suping Song, Zhanjie Li, Michael Kuok San Ho, Quang Le, Alexander M. Zeltser
  • Patent number: 10734015
    Abstract: The present disclosure generally relates to data storage devices, and more specifically, to a magnetic media drive employing a magnetic recording head. The head includes a main pole at a media facing surface (MFS), a trailing shield at the MFS, a heavy metal layer disposed between the main pole and the trailing shield at the MFS, and a yttrium-iron garnet (YIG) layer. Spin-orbit torque (SOT) is generated from the heavy metal layer and transferred to a surface of the main pole as a current passes through the heavy metal layer in a cross-track direction. The YIG layer is an electrical insulator, but also a good spin current conductor. Thus the charge current can be fully utilized for spin current conversion. The YIG layer does not dissipate energy because there is no shunting. With the reduced shunting from the main pole to the trailing shield, write-ability is improved.
    Type: Grant
    Filed: February 18, 2019
    Date of Patent: August 4, 2020
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Suping Song, Zhanjie Li, Michael Kuok San Ho
  • Publication number: 20200211584
    Abstract: Disclosed herein are circuits, architectures, and methods that provide for the control of a data storage device write head's trailing shield and main pole potential with respect to the disk using circuitry that is integrated with circuitry used to bias a spin torque oscillator (STO) apparatus. Various embodiments include slider connections with STO bias circuitry that resides in a read/write integrated circuit, which has a programmable circuit that generates a bias current with overshoot (bias kicks). Also disclosed are circuits that may be incorporated into a slider to mitigate radio-frequency interference.
    Type: Application
    Filed: March 11, 2020
    Publication date: July 2, 2020
    Applicant: Western Digital Technologies, Inc.
    Inventors: John CONTRERAS, Yunfei DING, Kuok San HO, Ian Robson MCFADYEN, Joey Martin POSS
  • Patent number: 10699734
    Abstract: A magnetic recording write head has an electrically-conductive structure in the write gap between the write pole and the trailing shield and electrical circuitry for directing current through the write gap. The current through the electrically-conductive structure generates a circular Ampere field which, at the disk-facing end of the write pole, is substantially parallel to the disk-facing end of the write pole. The electrically-conductive structure in the write gap may be a STO or an electrically-conductive layer that is not part of a STO. The current direction through the electrically-conductive structure in the write gap is selected so that the generated Ampere field at the write pole end is in substantially the same direction as the magnetization direction of the write head side shields, which has been discovered to result in minimization of cross-track interference.
    Type: Grant
    Filed: February 15, 2019
    Date of Patent: June 30, 2020
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Zhigang Bai, Alexander Taratorin, Anna Zheng, Venkatesh Chembrolu, Supradeep Narayana, Suping Song, Yaguang Wei, Terence Lam, Michael Kuok San Ho, Changqing Shi, Lijie Guan
  • Patent number: 10679650
    Abstract: A current-assisted magnetic recording write head has an electrically conductive layer in the write gap between the write pole and the trailing shield. Electrical circuitry directs current from the write pole, through the conductive layer, to the trailing shield. The current through the conductive layer generates an Ampere field substantially orthogonal to the magnetization in the write pole to assist magnetization switching of the write pole. The write head's magnetic throat height (THm) is substantially the thickness of the trailing shield at the write gap, while the write head's electrical throat height (THe) is substantially the height of the conductive layer in the write gap. In embodiments of this invention, the signal-to-noise ratio (SNR) of the readback signal and the soft error rate (SER) of the recorded data can be improved with a write gap structure wherein THe is greater than THm.
    Type: Grant
    Filed: February 15, 2019
    Date of Patent: June 9, 2020
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Zhigang Bai, Venkatesh Chembrolu, Yaguang Wei, Terence Lam, Michael Kuok San Ho, Lijie Guan, Suping Song, Supradeep Narayana
  • Publication number: 20200176022
    Abstract: A magnetic recording device includes a main pole, a coil around the main pole, a trailing shield, and a spin torque oscillation device between the main pole and the trailing shield. The spin torque oscillation device includes one or more first layers, a spacer layer, and a field generation layer. The one or more first layers are over the main pole. The one or more first layers have a first heat conductance or include a low-heat-conductance material. The spacer layer is over the one or more first layers. The field generation layer is over the spacer layer. A heat sink is in contact with the trailing shield. The heat sink has a second heat conductance or includes a high-heat-conductance material. The second heat conductance of the heat sink is higher than the first heat conductance of the one or more first layers.
    Type: Application
    Filed: June 25, 2019
    Publication date: June 4, 2020
    Inventors: Zhanjie LI, Suping SONG, Michael Kuok San HO