Patents by Inventor Zhitao Diao

Zhitao Diao 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: 20160180870
    Abstract: A tunnel magnetoresistance (TMR) read sensor having a tabbed AFM layer and an extended pinned layer and methods for making the same are provided. The TMR read sensor has an AFM layer recessed from the air bearing surface, providing a reduced shield-to-shield distance.
    Type: Application
    Filed: November 17, 2015
    Publication date: June 23, 2016
    Applicant: Western Digital (Fremont), LLC
    Inventors: SHAOPING LI, YUANKAI ZHENG, GERARDO A. BERTERO, QUNWEN LENG, MICHAEL L. MALLARY, RONGFU XIAO, MING MAO, ZHIHONG ZHANG, ANUP G. ROY, CHEN JUNG CHIEN, ZHITAO DIAO, LING WANG
  • Publication number: 20150380026
    Abstract: Systems and methods are provided for manufacturing a magnetic recording sensor for use in a magnetic reader, such as a tunneling magnetoresistance (TMR) readers. The magnetic recording sensor can be manufactured by heating a substrate in a first chamber and depositing an antiferromagnetic (AFM) layer on the heated substrate. Additionally, a first pinned layer is added onto the AFM layer, and the substrate is subsequently cooled.
    Type: Application
    Filed: September 3, 2015
    Publication date: December 31, 2015
    Inventors: YUANKAI ZHENG, QUNWEN LENG, TONG ZHAO, CHRISTIAN KAISER, ZHITAO DIAO, XIN JIANG
  • Patent number: 9214169
    Abstract: A method and system provide a magnetic transducer including a first shield, a read sensor, and a second shield. The read sensor is between the first shield and the second shield. The read sensor includes a pinned layer, a nonmagnetic spacer layer and a free layer. The nonmagnetic spacer layer is between the pinned layer and the free layer. The free layer includes a plurality of ferromagnetic layers interleaved with and sandwiching a plurality of nonmagnetic layers. The plurality of ferromagnetic layers are ferromagnetically aligned.
    Type: Grant
    Filed: June 20, 2014
    Date of Patent: December 15, 2015
    Assignee: Western Digital (Fremont), LLC
    Inventors: Christian Kaiser, Yuankai Zheng, Xin Jiang, Zhitao Diao, Qunwen Leng
  • Patent number: 9214172
    Abstract: A tunnel magnetoresistance (TMR) read sensor having a tabbed AFM layer and an extended pinned layer and methods for making the same are provided. The TMR read sensor has an AFM layer recessed from the air bearing surface, providing a reduced shield-to-shield distance.
    Type: Grant
    Filed: March 31, 2014
    Date of Patent: December 15, 2015
    Assignee: Western Digital (Fremont), LLC
    Inventors: Shaoping Li, Yuankai Zheng, Gerardo A. Bertero, Qunwen Leng, Michael L. Mallary, Rongfu Xiao, Ming Mao, Zhihong Zhang, Anup G. Roy, Chen Jung Chien, Zhitao Diao, Ling Wang
  • Patent number: 9147408
    Abstract: Systems and methods are provided for manufacturing a magnetic recording sensor for use in a magnetic reader, such as a tunneling magnetoresistance (TMR) readers. The magnetic recording sensor can be manufactured by heating a substrate in a first chamber and depositing an antiferromagnetic (AFM) layer on the heated substrate. Additionally, a first pinned layer is added onto the AFM layer, and the substrate is subsequently cooled.
    Type: Grant
    Filed: March 17, 2014
    Date of Patent: September 29, 2015
    Assignee: Western Digital (Fremont), LLC
    Inventors: Yuankai Zheng, Qunwen Leng, Tong Zhao, Christian Kaiser, Zhitao Diao, Xin Jiang
  • Patent number: 9042057
    Abstract: Methods for providing magnetic storage elements with high magneto-resistance using Heusler alloys are provided. One such method includes depositing a substrate including NiFe, depositing a seed layer on the substrate, depositing a buffer layer on the seed layer, and growing, epitaxially, an upper layer on the buffer layer, the upper layer including a Heusler alloy.
    Type: Grant
    Filed: May 29, 2014
    Date of Patent: May 26, 2015
    Assignee: Western Digital (Fremont), LLC
    Inventors: Zhitao Diao, Qunwen Leng
  • Publication number: 20150109702
    Abstract: A tunnel magnetoresistance (TMR) read sensor having a tabbed AFM layer and an extended pinned layer and methods for making the same are provided. The TMR read sensor has an AFM layer recessed from the air bearing surface, providing a reduced shield-to-shield distance.
    Type: Application
    Filed: March 31, 2014
    Publication date: April 23, 2015
    Applicant: Western Digital (Fremont), LLC
    Inventors: SHAOPING LI, YUANKAI ZHENG, GERARDO A. BERTERO, QUNWEN LENG, MICHAEL L. MALLARY, RONGFU XIAO, MING MAO, ZHIHONG ZHANG, ANUP G. ROY, CHEN JUNG CHIEN, ZHITAO DIAO, LING WANG
  • Patent number: 9007725
    Abstract: A magnetic sensor includes first and second ferromagnetic free layers that are not magnetically pinned, and a non-magnetic spacer layer disposed between them. The first ferromagnetic free layer comprises a first plurality of ferromagnetic sub-layers that includes a first cobalt iron sub-layer that is in contact with the non-magnetic spacer layer, and a first amorphous cobalt boron sub-layer that is not in contact with the non-magnetic spacer layer. The second ferromagnetic free layer comprises a second plurality of ferromagnetic sub-layers that includes a second cobalt iron sub-layer that is in contact with the non-magnetic spacer layer, and a second amorphous cobalt boron sub-layer that is not in contact with the non-magnetic spacer layer. Each of the first and second cobalt iron sub-layers has a composition Co(100?x)Fe(x) with x being in the range of 10 to 90 atomic percentage.
    Type: Grant
    Filed: October 7, 2014
    Date of Patent: April 14, 2015
    Assignee: Western Digital (Fremont), LLC
    Inventors: Zhitao Diao, Yuankai Zheng, Christian Kaiser, Qunwen Leng
  • Patent number: 8984740
    Abstract: A method for providing a magnetic recording transducer is provided. The method includes providing a substrate, and a magnetic shield having a top surface above the substrate. The top surface is treated by a first plasma treatment performed at a first power. An amorphous ferromagnetic (FM) layer is deposited on and in contact with the top surface to a thickness of at least 5 Angstroms and not more than 50 Angstroms. A second plasma treatment is performed at a second power. A magnetic seed layer is provided on and contact with the amorphous FM layer. The magnetic seed layer may comprise a bilayer. A nonmagnetic spacer layer is provided above the magnetic seed layer, an antiferromagnetic (AFM) layer provided above the spacer layer, and a read sensor provided above the AFM layer.
    Type: Grant
    Filed: November 30, 2012
    Date of Patent: March 24, 2015
    Assignee: Western Digital (Fremont), LLC
    Inventors: Yuankai Zheng, Qunwen Leng, Cheng-Han Yang, Zhitao Diao
  • Patent number: 8913350
    Abstract: A method and system for providing a magnetic element and a magnetic memory utilizing the magnetic element are described. The magnetic element is used in a magnetic device that includes a contact electrically coupled to the magnetic element. The method and system include providing pinned, nonmagnetic spacer, and free layers. The free layer has an out-of-plane demagnetization energy and a perpendicular magnetic anisotropy corresponding to a perpendicular anisotropy energy that is less than the out-of-plane demagnetization energy. The nonmagnetic spacer layer is between the pinned and free layers. The method and system also include providing a perpendicular capping layer adjoining the free layer and the contact. The perpendicular capping layer induces at least part of the perpendicular magnetic anisotropy in the free layer. The magnetic element is configured to allow the free layer to be switched between magnetic states when a write current is passed through the magnetic element.
    Type: Grant
    Filed: August 10, 2009
    Date of Patent: December 16, 2014
    Assignee: Grandis, Inc.
    Inventors: Steven M. Watts, Zhitao Diao, Xueti Tang
  • Patent number: 8760818
    Abstract: Systems and methods for providing magnetic storage elements with high magneto-resistance using Heusler alloys are provided. One such method includes depositing a substrate including NiFe, depositing a seed layer on the substrate, depositing a buffer layer on the seed layer, and growing, epitaxially, an upper layer on the buffer layer, the upper layer including a Heusler alloy.
    Type: Grant
    Filed: January 9, 2013
    Date of Patent: June 24, 2014
    Assignee: Western Digital (Fremont), LLC
    Inventors: Zhitao Diao, Qunwen Leng
  • Publication number: 20140151829
    Abstract: A magnetic element and a magnetic memory utilizing the magnetic element are described. A contact is electrically coupled to the magnetic element. The magnetic element includes pinned, nonmagnetic spacer, and free layers and a perpendicular capping layer adjoining the free layer and the contact. The free layer has an out-of-plane demagnetization energy and a perpendicular magnetic anisotropy corresponding to a perpendicular anisotropy energy that is less than the out-of-plane demagnetization energy. The nonmagnetic spacer layer is between the pinned and free layers. The perpendicular capping layer induces at least part of the perpendicular magnetic anisotropy. The free layer is switchable between magnetic states when a write current is passed through the magnetic element. The free layer includes ferromagnetic layers interleaved with capping layer(s) such that a ferromagnetic layer resides at an edge of the free layer.
    Type: Application
    Filed: February 10, 2014
    Publication date: June 5, 2014
    Applicant: Samsung Electronics Co., LTD.
    Inventors: Steven M. Watts, Zhitao Diao, Xueti Tang
  • Patent number: 8582253
    Abstract: A magnetic sensor configured to reside in proximity to a recording medium during use having a high spin polarization reference layer stack above AFM layers. The reference layer stack comprises a first boron-free ferromagnetic layer above the AFM coupling layer; a magnetic coupling layer on and in contact with the first boron-free ferromagnetic layer; a second ferromagnetic layer comprising boron deposited on and contact with the magnetic coupling layer; and a boron-free third ferromagnetic layer on and in contact the second ferromagnetic layer. A barrier layer is deposited on and in contact with the boron-free third ferromagnetic layer. In one aspect of the invention, the magnetic coupling layer may comprise at least one of Ta, Ti, or Hf. A process for providing the magnetic sensor is also provided.
    Type: Grant
    Filed: June 4, 2012
    Date of Patent: November 12, 2013
    Assignee: Western Digital (Fremont), LLC
    Inventors: Yuankai Zheng, Qunwen Leng, Mahendra Pakala, Zhitao Diao, Christian Kaiser, Cheng-Han Yang
  • Patent number: 8476723
    Abstract: A magnetic device including a magnetic element is described. The magnetic element includes a fixed layer having a fixed layer magnetization, a spacer layer that is nonmagnetic, and a free layer having a free layer magnetization. The free layer is changeable due to spin transfer when a write current above a threshold is passed through the first free layer. The free layer is includes low saturation magnetization materials.
    Type: Grant
    Filed: June 14, 2011
    Date of Patent: July 2, 2013
    Assignees: Grandis, Inc., Renesas Electronics Corporation
    Inventors: Hide Nagai, Zhitao Diao, Yiming Huai
  • Publication number: 20120155156
    Abstract: A method and system for providing a magnetic element and a magnetic memory utilizing the magnetic element are described. The magnetic element is used in a magnetic device that includes a contact electrically coupled to the magnetic element. The method and system include providing pinned, nonmagnetic spacer, and free layers. The free layer has an out-of-plane demagnetization energy and a perpendicular magnetic anisotropy corresponding to a perpendicular anisotropy energy that is less than the out-of-plane demagnetization energy. The nonmagnetic spacer layer is between the pinned and free layers. The method and system also include providing a perpendicular capping layer adjoining the free layer and the contact. The perpendicular capping layer induces at least part of the perpendicular magnetic anisotropy in the free layer. The magnetic element is configured to allow the free layer to be switched between magnetic states when a write current is passed through the magnetic element.
    Type: Application
    Filed: February 25, 2011
    Publication date: June 21, 2012
    Applicant: Grandis, Inc.
    Inventors: Steven M. Watts, Zhitao Diao, Xueti Tang, Kiseok Moon, Mohamad Towfik Krounbi
  • Publication number: 20110241141
    Abstract: A magnetic device including a magnetic element is described. The magnetic element includes a fixed layer having a fixed layer magnetization, a spacer layer that is nonmagnetic, and a free layer having a free layer magnetization. The free layer is changeable due to spin transfer when a write current above a threshold is passed through the first free layer. The free layer is includes low saturation magnetization materials.
    Type: Application
    Filed: June 14, 2011
    Publication date: October 6, 2011
    Applicants: RENESAS TECHNOLOGY CORPORATION, GRANDIS INC.
    Inventors: Hide Nagai, Zhitao Diao, Yiming Huai
  • Patent number: 7982275
    Abstract: A magnetic device including a magnetic element is described. The magnetic element includes a fixed layer having a fixed layer magnetization, a spacer layer that is nonmagnetic, and a free layer having a free layer magnetization. The free layer is changeable due to spin transfer when a write current above a threshold is passed through the first free layer. The free layer is includes low saturation magnetization materials.
    Type: Grant
    Filed: August 22, 2007
    Date of Patent: July 19, 2011
    Assignees: Grandis Inc., Renesas Technology Corporation
    Inventors: Hide Nagai, Zhitao Diao, Yiming Huai
  • Patent number: 7973349
    Abstract: Magnetic multilayer structures, such as magnetic or magnetoresistive tunnel junctions (MTJs) and spin valves, having a magnetic biasing layer formed next to and magnetically coupled to the free ferromagnetic layer to achieve a desired stability against fluctuations caused by, e.g., thermal fluctuations and astray fields. Stable MTJ cells with low aspect ratios can be fabricated using CMOS processing for, e.g., high-density MRAM memory devices and other devices, using the magnetic biasing layer. Such multilayer structures can be programmed using spin transfer induced switching by driving a write current perpendicular to the layers. Each free ferromagnetic layer can include two or more layers and may be a multilayered free ferromagnetic stack that includes first and second ferromagnetic layers and a non-magnetic spacer between the first and second ferromagnetic layers.
    Type: Grant
    Filed: August 1, 2006
    Date of Patent: July 5, 2011
    Assignee: Grandis Inc.
    Inventors: Yiming Huai, Zhitao Diao, Eugene Youjun Chen
  • Patent number: 7916433
    Abstract: A method and system for providing a magnetic element are described. The method and system include providing a pinned layer, a barrier layer, and a free layer. The free layer includes a first ferromagnetic layer, a second ferromagnetic layer, and an intermediate layer between the first ferromagnetic layer and the second ferromagnetic layer. The barrier layer resides between the pinned layer and the free layer and includes MgO. The first ferromagnetic layer resides between the barrier layer and the intermediate layer. The first ferromagnetic layer includes at least one of CoFeX and CoNiFeX, with X being selected from the group of B, P, Si, Nb, Zr, Hf, Ta, Ti, and being greater than zero atomic percent and not more than thirty atomic percent. The first ferromagnetic layer is ferromagnetically coupled with the second ferromagnetic layer.
    Type: Grant
    Filed: June 15, 2010
    Date of Patent: March 29, 2011
    Assignee: Grandis, Inc.
    Inventors: Yiming Huai, Zhitao Diao, Eugene Youjun Chen
  • Patent number: 7888755
    Abstract: A storage element 3 has an arrangement in which magnetization fixed layers 31 and 32 are provided above and below a storage layer 17 for storing information based on the magnetization state of a magnetic material through intermediate layers 16 and 18, directions of magnetizations M15 and M19 of ferromagnetic layers 15 and 19 closest to the storage layer 17 of the magnetization fixed layers 31 and 32 above and below the storage layer 17 are opposite to each other, the two intermediate layers 16 and 18 above and below the storage layer 17 have a significant difference between sheet resistivity values thereof and in which the direction of a magnetization M1 of the storage layer 17 is changed with application of an electric current to the lamination layer direction to record information on the storage layer 17.
    Type: Grant
    Filed: September 26, 2005
    Date of Patent: February 15, 2011
    Assignee: Sony Corporation
    Inventors: Masanori Hosomi, Kazuhiro Ohba, Hiroshi Kano, Yiming Huai, Zhitao Diao, Mahendra Pakala