Patents by Inventor Cherngye Hwang

Cherngye Hwang 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: 20240144965
    Abstract: The present disclosure generally relates to spin-orbit torque (SOT) devices comprising a bismuth antimony (BiSb) layer. The SOT devices further comprises a first shield, a BiSb layer disposed over the first shield (S1), a free layer (FL) disposed over the BiSb layer, and a second shield (S2) disposed over the FL. The S1, the FL, and the S2 are disposed at a media facing surface (MFS). The BiSb layer is recessed from the MFS a first distance of about 5 nm to about 20 nm. The FL has a length greater than the first distance. A notch and/or an insulation layer is disposed adjacent to the BiSb layer at the MFS. Current may be configured to flow vertically through the S2 to the FL, and horizontally from the FL to the BiSb layer. Current may be configured to flow vertically through the S2 to the S1.
    Type: Application
    Filed: July 31, 2023
    Publication date: May 2, 2024
    Applicant: Western Digital Technologies, Inc.
    Inventors: Quang LE, Rohan Babu NAGABHIRAVA, Xiaoyong LIU, Brian R. YORK, Cherngye HWANG, Son T. LE, Randy G. SIMMONS, Kuok San HO, Hisashi TAKANO
  • Publication number: 20240144960
    Abstract: The present disclosure generally relates to a two dimensional magnetic recording (TDMR) spin-orbit torque (SOT) read head comprising bismuth antimony (BiSb) layers. The read head comprises a lower reader comprising a first SOT stack and an upper reader comprising a second SOT stack. The first SOT stack and the second SOT stack each individually comprise a BiSb layer recessed from a media facing surface (MFS) and a free layer exposed at the MFS. The BiSb layers of each SOT stack are recessed from the MFS a distance of about 5 nm to about 20 nm, the distance being less than a length of the free layers. In one embodiment, the lower reader and the upper reader share a current path. In another embodiment, the lower reader and the upper reader have separate current paths.
    Type: Application
    Filed: July 26, 2023
    Publication date: May 2, 2024
    Applicant: Western Digital Technologies, Inc.
    Inventors: Quang LE, Rohan Babu NAGABHIRAVA, Xiaoyong LIU, Brian R. YORK, Son T. LE, Cherngye HWANG, Kuok San HO, Hisashi TAKANO
  • Publication number: 20240112840
    Abstract: Embodiments of the present disclosure relate to a cobalt-boron (CoB) layer for magnetic recording devices, memory devices, and storage devices. In one or more embodiments, the CoB layer is part of a spin-orbit torque (SOT) device. In one or more embodiments, the SOT device is part of an SOT based sensor, an SOT based writer, a memory device (such as a magnetoresistive random-access memory (MRAM) device), and/or a storage device (such as a hard disk drive (HDD) or a tape drive). In one embodiment, an SOT device includes a seed layer, and a cap layer spaced from the seed layer. The SOT device includes a spin-orbit torque (SOT) layer, and a nano layer (NL) between the seed layer and the cap layer. The SOT device includes a cobalt-boron (CoB) layer between the seed layer and the cap layer, and the CoB layer is ferromagnetic.
    Type: Application
    Filed: September 29, 2022
    Publication date: April 4, 2024
    Applicant: Western Digital Technologies, Inc.
    Inventors: Susumu OKAMURA, Quang LE, Brian R. YORK, Cherngye HWANG, Randy G. SIMMONS, Kuok San HO, Hisashi TAKANO
  • Patent number: 11908496
    Abstract: The present disclosure generally relate to spin-orbit torque (SOT) devices comprising a topological insulator (TI) modulation layer. The TI modulation layer comprises a plurality of bismuth or bismuth-rich composition modulation layers, a plurality of TI lamellae layers comprising BiSb having a (012) crystal orientation, and a plurality of texturing layers. The TI lamellae layers comprise dopants or clusters of atoms, the clusters of atoms comprising a carbide, a nitride, an oxide, or a composite ceramic material. The clusters of atoms are configured to have a grain boundary glass forming temperature of less than about 400° C. Doping the TI lamellae layers comprising BiSb having a (012) crystal orientation with clusters of atoms comprising a carbide, a nitride, an oxide, or a composite ceramic material enable the SOT MTJ device to operate at higher temperatures while inhibiting migration of Sb from the BiSb of the TI lamellae layers.
    Type: Grant
    Filed: December 16, 2022
    Date of Patent: February 20, 2024
    Assignee: Western Digital Technologies, Inc.
    Inventors: Quang Le, Brian R. York, Cherngye Hwang, Susumu Okamura, Xiaoyong Liu, Kuok San Ho, Hisashi Takano
  • Publication number: 20240032437
    Abstract: The present disclosure generally relates to spin-orbit torque (SOT) devices comprising a bismuth antimony (BiSb) layer. The SOT devices further comprises a nonmagnetic buffer layer, a nonmagnetic interlayer, a ferromagnetic layer, and a nonmagnetic barrier layer. One or more of the barrier layer, interlayer, and buffer layer comprise a polycrystalline non-Heusler alloy material, or a Heusler alloy and a material selected from the group consisting of: Cu, Ag, Ge, Mn, Ni, Co, Mo, W, Sn, B, and In. The Heusler alloy is a full Heusler alloy comprising X2YZ or a half Heusler alloy comprising XYZ, where X is one of: Mn, Fe, Co, Ni, Cu, Ru, Rh, Pd, Ag, Ir, Pt, and Au, Y is one of: Ti, V, Cr, Mn, Fe, Co, Ni, Zn, Y, Zr, Nb, Mo, Hf, and W, and Z is one of: B, Al, Si, Ga, Ge, As, In, Sn, Sb, and Bi.
    Type: Application
    Filed: May 15, 2023
    Publication date: January 25, 2024
    Applicant: Western Digital Technologies, Inc.
    Inventors: Quang LE, Brian R. YORK, Cherngye HWANG, Xiaoyong LIU, Susumu OKAMURA, Michael A. GRIBELYUK, Xiaoyu XU, Randy G. SIMMONS, Kuok San HO, Hisashi TAKANO
  • Patent number: 11875827
    Abstract: The present disclosure generally relate to spin-orbit torque (SOT) devices. The SOT devices each comprise a non-magnetic layer, a free layer disposed in contact with the non-magnetic layer, and a bismuth antimony (BiSb) layer disposed over the free layer. The non-magnetic layer has a thickness of about 0.5 nm to about 2 nm. The BiSb layer has a thickness of about 5 nm to about 10 nm. The BiSb layer and the free layer have collective thickness between about 5 nm to about 20 nm. By reducing the thickness of the non-magnetic layer and BiSb layer, a read gap of each SOT device is reduced while enabling large inverse spin Hall angles and high signal-to-noise ratios.
    Type: Grant
    Filed: March 25, 2022
    Date of Patent: January 16, 2024
    Assignee: Western Digital Technologies, Inc.
    Inventors: Quang Le, Brian R. York, Xiaoyong Liu, Son T. Le, Cherngye Hwang, Michael A. Gribelyuk, Xiaoyu Xu, Kuok San Ho, Hisashi Takano, Julian Sasaki, Huy H. Ho, Khang H. D. Nguyen, Nam Hai Pham
  • Publication number: 20240006109
    Abstract: The present disclosure generally relates to spin-orbit torque (SOT) device comprising a first bismuth antimony (BiSb) layer having a (001) orientation. The SOT device comprises a first BiSb layer having a (001) orientation and a second BiSb layer having a (012) orientation. The first BiSb layer having a (001) orientation is formed by depositing an amorphous material selected from the group consisting of: B, Al, Si, SiN, Mg, Ti, Sc, V, Cr, Mn, Y, Zr, Nb, AlN, C, Ge, and combinations thereof, on a substrate, exposing the amorphous material to form an amorphous oxide surface on the amorphous material, and depositing the first BiSb layer on the amorphous oxide surface. By utilizing a first BiSb layer having a (001) orientation and a second BiSb having a (012) orientation, the signal through the SOT device is balanced and optimized to match through both the first and second BiSb layers.
    Type: Application
    Filed: June 30, 2022
    Publication date: January 4, 2024
    Applicant: Western Digital Technologies, Inc.
    Inventors: Quang LE, Brian R. YORK, Cherngye HWANG, Xiaoyong LIU, Michael A. GRIBELYUK, Xiaoyu XU, Randy G. SIMMONS, Kuok San HO, Hisashi TAKANO
  • Publication number: 20240005973
    Abstract: The present disclosure generally relates to spin-orbit torque (SOT) devices comprising a bismuth antimony (BiSb) layer. The SOT devices further comprise one or more GexNiFe layers, where at least one GexNiFe layer is disposed in contact with the BiSb layer. The GexNiFe layer has a thickness less than or equal to about 15 ? when used as an interlayer on top of the BiSb layer or less than or equal to 40 ? when used as a buffer layer underneath the BiSb. When the BiSb layer is doped with a dopant comprising a gas, a metal, a non-metal, or a ceramic material, the GexNiFe layer promotes the BiSb layer to have a (012) orientation. When the BiSb layer is undoped, the GexNiFe layer promotes the BiSb layer to have a (001) orientation. Utilizing the GexNiFe layer allows the crystal orientation of the BiSb layer to be selected.
    Type: Application
    Filed: June 30, 2022
    Publication date: January 4, 2024
    Applicant: Western Digital Technologies, Inc.
    Inventors: Quang LE, Brian R. YORK, Cherngye HWANG, Xiaoyong LIU, Michael A. GRIBELYUK, Xiaoyu XU, Susumu OKAMURA, Kuok San HO, Hisashi TAKANO, Randy G. SIMMONS
  • Publication number: 20230419990
    Abstract: The present disclosure generally relates to a bismuth antimony (BiSb) based STO (spin torque oscillator) sensor. The STO sensor comprises a SOT device and a magnetic tunnel junction (MTJ) structure. By utilizing a BiSb layer within the SOT device, a larger spin Hall angle (SHA) can be achieved, thereby improving the efficiency and reliability of the STO sensor.
    Type: Application
    Filed: September 11, 2023
    Publication date: December 28, 2023
    Applicant: Western Digital Technologies, Inc.
    Inventors: Xiaoyong LIU, Zhanjie LI, Quang LE, Brian R. YORK, Cherngye HWANG, Kuok San HO, Hisashi TAKANO
  • Publication number: 20230386721
    Abstract: The present disclosure generally relate to spin-orbit torque (SOT) magnetic tunnel junction (MTJ) devices comprising a buffer layer, a bismuth antimony (BiSb) layer having a (012) orientation disposed on the buffer layer, and an interlayer disposed on the BiSb layer. The buffer layer and the interlayer may each independently be a single layer of material or a multilayer of material. The buffer layer and the interlayer each comprise at least one of a covalently bonded amorphous material, a tetragonal (001) material, a tetragonal (110) material, a body-centered cubic (bcc) (100) material, a face-centered cubic (fcc) (100) material, a textured bcc (100) material, a textured fcc (100) material, a textured (100) material, or an amorphous metallic material. The buffer layer and the interlayer inhibit antimony (Sb) migration within the BiSb layer and enhance uniformity of the BiSb layer while further promoting the (012) orientation of the BiSb layer.
    Type: Application
    Filed: August 9, 2023
    Publication date: November 30, 2023
    Applicant: Western Digital Technologies, Inc.
    Inventors: Quang LE, Brian R. YORK, Cherngye HWANG, Susumu OKAMURA, Michael A. GRIBELYUK, Xiaoyong LIU, Kuok San HO, Hisashi TAKANO
  • Patent number: 11783853
    Abstract: The present disclosure generally relates to a bismuth antimony (BiSb) based STO (spin torque oscillator) sensor. The STO sensor comprises a SOT device and a magnetic tunnel junction (MTJ) structure. By utilizing a BiSb layer within the SOT device, a larger spin Hall angle (SHA) can be achieved, thereby improving the efficiency and reliability of the STO sensor.
    Type: Grant
    Filed: May 31, 2022
    Date of Patent: October 10, 2023
    Assignee: Western Digital Technologies, Inc.
    Inventors: Xiaoyong Liu, Zhanjie Li, Quang Le, Brian R. York, Cherngye Hwang, Kuok San Ho, Hisashi Takano
  • Patent number: 11776567
    Abstract: The present disclosure generally relates to spin-orbital torque (SOT) differential reader designs. The SOT differential reader is a multi-terminal device comprising a first seed layer, a first spin hall effect (SHE) layer, a first interlayer, a first free layer, a gap layer, a second seed layer, a second SHE layer, a second free layer, and a second interlayer. The gap layer is disposed between the first SHE layer and the second SHE layer. The materials and dimensions used for the first and second seed layers, the first and second interlayers, and the first and second SHE layers affect the resulting spin hall voltage converted from spin current injected from the first free layer and the second free layer, as well as the ability to tune the first and second SHE layers. Moreover, the SOT differential reader improves reader resolution without decreasing the shield-to-shield spacing (i.e., read-gap).
    Type: Grant
    Filed: August 5, 2021
    Date of Patent: October 3, 2023
    Assignee: Western Digital Technologies, Inc.
    Inventors: Cherngye Hwang, Xiaoyong Liu, Quang Le, Kuok San Ho, Hisashi Takano, Brian R. York
  • Patent number: 11776565
    Abstract: The present disclosure generally relates to a tape head of a tape drive, and methods of forming thereof. In one embodiment, a tape head for magnetic storage devices comprises a trailing shield, a leading shield, a first write pole coupled to the trailing shield, a second write pole coupled to the leading shield, and side shields spaced from the first write pole and the second write pole by a thin insulation layer. The side shields are further disposed between the trailing shield and the leading shield. In another embodiment, a tape head for magnetic storage devices comprises a main pole disposed between a trailing shield and a leading shield and a side shield disposed adjacent to the main pole. The side shield is further disposed between the trailing shield and the leading shield and spaced from the main pole by a thin insulation layer.
    Type: Grant
    Filed: January 12, 2022
    Date of Patent: October 3, 2023
    Assignee: Western Digital Technologies, Inc.
    Inventors: Quang Le, Hongquan Jiang, Cherngye Hwang, David J. Seagle, Xiaoyong Liu
  • Publication number: 20230306993
    Abstract: The present disclosure generally relate to spin-orbit torque (SOT) devices. The SOT devices each comprise a non-magnetic layer, a free layer disposed in contact with the non-magnetic layer, and a bismuth antimony (BiSb) layer disposed over the free layer. The non-magnetic layer has a thickness of about 0.5 nm to about 2 nm. The BiSb layer has a thickness of about 5 nm to about 10 nm. The BiSb layer and the free layer have collective thickness between about 5 nm to about 20 nm. By reducing the thickness of the non-magnetic layer and BiSb layer, a read gap of each SOT device is reduced while enabling large inverse spin Hall angles and high signal-to-noise ratios.
    Type: Application
    Filed: March 25, 2022
    Publication date: September 28, 2023
    Inventors: Quang LE, Brian R. YORK, Xiaoyong LIU, Son T. LE, Cherngye HWANG, Michael A. GRIBELYUK, Xiaoyu XU, Kuok San HO, Hisashi TAKANO, Julian SASAKI, Huy H. HO, Khang H. D. NGUYEN, Nam Hai PHAM
  • Patent number: 11763973
    Abstract: The present disclosure generally relate to spin-orbit torque (SOT) magnetic tunnel junction (MTJ) devices comprising a buffer layer, a bismuth antimony (BiSb) layer having a (012) orientation disposed on the buffer layer, and an interlayer disposed on the BiSb layer. The buffer layer and the interlayer may each independently be a single layer of material or a multilayer of material. The buffer layer and the interlayer each comprise at least one of a covalently bonded amorphous material, a tetragonal (001) material, a tetragonal (110) material, a body-centered cubic (bcc) (100) material, a face-centered cubic (fcc) (100) material, a textured bcc (100) material, a textured fcc (100) material, a textured (100) material, or an amorphous metallic material. The buffer layer and the interlayer inhibit antimony (Sb) migration within the BiSb layer and enhance uniformity of the BiSb layer while further promoting the (012) orientation of the BiSb layer.
    Type: Grant
    Filed: August 13, 2021
    Date of Patent: September 19, 2023
    Assignee: Western Digital Technologies, Inc.
    Inventors: Quang Le, Brian R. York, Cherngye Hwang, Susumu Okamura, Michael Gribelyuk, Xiaoyong Liu, Kuok San Ho, Hisashi Takano
  • Patent number: 11735211
    Abstract: The present disclosure relates to read head apparatus, and methods of forming read head apparatus, for magnetic storage devices, such as magnetic tape drives (e.g., tape drives). In one implementation, a read head for magnetic storage devices includes a lower shield, one or more upper shields, one or more lower leads, and a plurality of upper leads. The read head includes a plurality of read sensors, each read sensor of the plurality of read sensors including a first antiferromagnetic (AFM) layer. The read head includes a plurality of soft bias side shields disposed between and outwardly of the plurality of read sensors. The read head includes one or more second AFM layers disposed above the first AFM layer and the plurality of soft bias side shields along a downtrack direction.
    Type: Grant
    Filed: July 18, 2022
    Date of Patent: August 22, 2023
    Assignee: Western Digital Technologies, Inc.
    Inventors: Quang Le, Hongquan Jiang, Cherngye Hwang, Hisashi Takano
  • Publication number: 20230238179
    Abstract: The present disclosure generally relates to a storage device comprising soft bias structures having high coercivity and high anisotropy, and a method of forming thereof. The soft bias structures may be formed by moving a wafer in a first direction under a plume of NiFe to deposit a first NiFe layer at a first angle, moving the wafer in a second direction anti-parallel to the first direction to deposit a second NiFe layer at a second angle on the first NiFe layer, and repeating one or more times. The soft bias structures may be formed by rotating a wafer to a first position, depositing a first NiFe layer at a first angle, rotating the wafer to a second position, depositing a second NiFe layer at a second angle on the first NiFe layer, and repeating one or more times. The first and second NiFe layers have different grain structures.
    Type: Application
    Filed: April 3, 2023
    Publication date: July 27, 2023
    Applicant: Western Digital Technologies, Inc.
    Inventors: Masaya NISHIOKA, Diane L. BROWN, Jianhua HU, Cherngye HWANG
  • Publication number: 20230223043
    Abstract: The present disclosure generally relates to a tape head of a tape drive, and methods of forming thereof. In one embodiment, a tape head for magnetic storage devices comprises a trailing shield, a leading shield, a first write pole coupled to the trailing shield, a second write pole coupled to the leading shield, and side shields spaced from the first write pole and the second write pole by a thin insulation layer. The side shields are further disposed between the trailing shield and the leading shield. In another embodiment, a tape head for magnetic storage devices comprises a main pole disposed between a trailing shield and a leading shield and a side shield disposed adjacent to the main pole. The side shield is further disposed between the trailing shield and the leading shield and spaced from the main pole by a thin insulation layer.
    Type: Application
    Filed: January 12, 2022
    Publication date: July 13, 2023
    Applicant: Western Digital Technologies, Inc.
    Inventors: Quang LE, Hongquan JIANG, Cherngye HWANG, David J. SEAGLE, Xiaoyong LIU
  • Patent number: 11694713
    Abstract: A spin-orbit torque (SOT) magnetic tunnel junction (MTJ) device includes a substrate, a buffer layer formed over the substrate, and a bismuth antimony (BiSb) layer formed over the buffer layer, the BiSb layer having a (012) orientation. In certain embodiments, the SOT MTJ device is part of a microwave assisted magnetic recording (MAMR) write head. In certain embodiments, the SOT MTJ device is part of a magnetoresistive random access memory (MRAM) device.
    Type: Grant
    Filed: November 20, 2020
    Date of Patent: July 4, 2023
    Assignee: Western Digital Technologies, Inc.
    Inventors: Quang Le, Cherngye Hwang, Brian R. York, Thao A. Nguyen, Zheng Gao, Kuok San Ho, Pham Nam Hai
  • Publication number: 20230197132
    Abstract: The present disclosure generally relates to spin-orbit torque (SOT) magnetic tunnel junction (MTJ) devices comprising a doped bismuth antimony (BiSbE) layer having a (012) orientation. The devices may include magnetic write heads, read heads, or MRAM devices. The dopant in the BiSbE layer enhances the (012) orientation. The BiSbE layer may be formed on a texturing layer to ensure the (012) orientation, and a migration barrier may be formed over the BiSbE layer to ensure the antimony does not migrate through the structure and contaminate other layers. A buffer layer and interlayer may also be present. The buffer layer and the interlayer may each independently be a single layer of material or a multilayer of material. The buffer layer and the interlayer inhibit antimony (Sb) migration within the doped BiSbE layer and enhance uniformity of the doped BiSbE layer while further promoting the (012) orientation of the doped BiSbE layer.
    Type: Application
    Filed: June 30, 2022
    Publication date: June 22, 2023
    Applicant: Western Digital Technologies, Inc.
    Inventors: Quang LE, Cherngye HWANG, Brian R. YORK, Randy G. SIMMONS, Xiaoyong LIU, Kuok San HO, Hisashi TAKANO, Michael A. GRIBELYUK, Xiaoyu XU