Patents by Inventor Tong Zhao

Tong Zhao 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).

  • TMR Device with Novel Free Layer Structure
    Publication number: 20150248902
    Abstract: A TMR sensor that includes a free layer having at least one B-containing (BC) layer made of CoFeB, CoFeBM, CoB, CoBM, or CoBLM, and a plurality of non-B containing (NBC) layers made of CoFe, CoFeM, or CoFeLM is disclosed where L and M are one of Ni, Ta, Ti, W, Zr, Hf, Tb, or Nb. One embodiment is represented by (NBC/BC)n where n?2. A second embodiment is represented by (NBC/BC)n/NBC where n?1. In every embodiment, a NBC layer contacts the tunnel barrier and NBC layers each with a thickness from 2 to 8 Angstroms are formed in alternating fashion with one or more BC layers each 10 to 80 Angstroms thick. Total free layer thickness is <100 Angstroms. The free layer configuration described herein enables a significant noise reduction (SNR enhancement) while realizing a high TMR ratio, low magnetostriction, low RA, and low Hc values.
    Type: Application
    Filed: May 15, 2015
    Publication date: September 3, 2015
    Inventors: Tong Zhao, Hui-Chuan Wang, Yu-Chen Zhou, Min Li, Kunliang Zhang
  • Control systems and methods for controlling a dry feed system to convey a solid fuel
    Patent number: 9122280
    Abstract: A control system for controlling a dry feed system to convey a solid fuel includes multiple sensors, a pressurizing gas controller, at least one assistant gas controller and multiple gas valves. The sensors generate multiple measurement signals signifying characteristics of the dry feed system. The pressuring gas controller calculates a feed tank pressure bias or/and a pressuring gas flow bias based on a solid flow rate and generates a first control signal based on the pressure bias or/and the pressurizing gas flow bias. The assistant gas controller calculates an assistant gas bias based on a solid loading ratio and generates a second control signal based on the assistant gas bias. The gas valves are driven by the first or/and second control signals to regulate the solid fuel. A control method is also described.
    Type: Grant
    Filed: May 20, 2011
    Date of Patent: September 1, 2015
    Assignee: GENERAL ELECTRIC COMPANY
    Inventors: Xu Fu, Zhongzhi Hu, Tong Zhao, Zili Cai, Yao Chen, Baoming Huang, Wei Chen, Ke Liu
  • TMR Device with Low Magnetostriction Free Layer
    Publication number: 20150235660
    Abstract: A high performance TMR sensor is fabricated by employing a free layer comprised of CoNiFeB or CoNiFeBM where M is V, Ti, Zr, Nb, Hf, Ta, or Mo and the M content in the alloy is <10 atomic %. The free layer may have a FeCo/FeB/CoNiFeB, FeCo/CoFe/CoNiFeB, FeCo/CoFeB/CoNiFeB, or FeCo/CoNiFeB/CoFeB configuration. A CoNiFeBM layer may be formed by co-sputtering CoB with CoNiFeM. A 15 to 30% in improvement in TMR ratio over a conventional CoFe/NiFe free layer is achieved while maintaining low Hc and RA<3 ohm-um2. The CoNiFeB or CoNiFeBM layer has a magnetostriction (?) value between ?5×10?6 and 5×10?6.
    Type: Application
    Filed: April 29, 2015
    Publication date: August 20, 2015
    Inventors: Hui-Chuan Wang, Tong Zhao, Min Li, Kunliang Zhang
  • DEVICES INCLUDING AT LEAST ONE INTERMIXING LAYER
    Publication number: 20150179194
    Abstract: Devices that include a near field transducer (NFT), the NFT including a peg having five surfaces, the peg including a first material, the first material including gold (Au), silver (Ag), aluminum (Al), copper (Cu), ruthenium (Ru), rhodium (Rh), iridium (Ir), or combinations thereof; an overlying structure; and at least one intermixing layer, positioned between the peg and the overlying structure, the at least one intermixing layer positioned on at least one of the five surfaces of the peg, the intermixing layer including at least the first material and a second material.
    Type: Application
    Filed: February 26, 2015
    Publication date: June 25, 2015
    Inventors: Yuhang Cheng, Tong Zhao, Michael C. Kautzky, Ed F. Rejda, Kurt W. Wierman, Scott Franzen, Michael Allen Seigler
  • Near field transducer and heat sink design for heat assisted magnetic recording
    Patent number: 9064515
    Abstract: Apparatuses, systems, and methods are disclosed related to heat assisted magnetic recording. According to one embodiment, an apparatus that includes a heat sink region and a near field transducer region is disclosed. The near field transducer region is thermally coupled to the heat sink region. At least one of the heat sink region and the near field transducer region includes both an inner core and an outer shell. The inner core can be comprised of a non-plasmonic material and the outer shell can be comprised of a plasmonic material. In further embodiments, the inner core is comprised of a material having a relatively higher electron-phonon coupling constant and the outer shell is comprised of a material having a relatively lower electron-phonon coupling constant.
    Type: Grant
    Filed: May 23, 2014
    Date of Patent: June 23, 2015
    Assignee: SEAGATE TECHNOLOGY LLC
    Inventors: Tong Zhao, John C. Duda, Michael Christopher Kautzky
  • DEVICES INCLUDING AT LEAST ONE ADHESION LAYER AND METHODS OF FORMING ADHESION LAYERS
    Publication number: 20150170684
    Abstract: Devices that include a near field transducer (NFT), the NFT having a disc and a peg, and the peg having an air bearing surface; and at least one adhesion layer positioned on the air bearing surface of the peg, the adhesion layer including one or more of the following: tungsten (W), molybdenum (Mo), chromium (Cr), silicon (Si), nickel (Ni), tantalum (Ta), titanium (Ti), yttrium (Y), vanadium (V), magnesium (Mg), cobalt (Co), tin (Sn), niobium (Nb), hafnium (Hf), and combinations thereof; tantalum oxide, titanium oxide, tin oxide, indium oxide, and combinations thereof; vanadium carbide (VC), tungsten carbide (WC), titanium carbide (TiC), chromium carbide (CrC), cobalt carbide (CoC), nickel carbide (NiC), yttrium carbide (YC), molybdenum carbide (MoC), and combinations thereof and titanium nitride (TiN), zirconium nitride (ZrN), hafnium nitride (HfN), and combinations thereof.
    Type: Application
    Filed: February 26, 2015
    Publication date: June 18, 2015
    Inventors: Yuhang Cheng, Tong Zhao, Michael C. Kautzky, Ed F. Rejda, Kurt W. Wierman, Scott Franzen, Andrew J. Boyne, Michael Allen Seigler, Sethuraman Jayashankar
  • HEAT ASSISTED MAGNETIC RECORDING HEADS HAVING BILAYER HEAT SINKS
    Publication number: 20150154989
    Abstract: Disclosed herein is an apparatus that includes a near field transducer positioned adjacent to an air bearing surface of the apparatus; a first magnetic pole; and a heat sink positioned between the first magnetic pole and the near field transducer, wherein the heat sink includes a first and second portion, with the first portion being adjacent the near field transducer and the second portion being adjacent the first magnetic pole, the first portion including a plasmonic material, and the second portion including a diffusion blocking material.
    Type: Application
    Filed: December 1, 2014
    Publication date: June 4, 2015
    Inventors: Tong Zhao, Ibro Tabakovic, Michael C. Kautzky, Venkatram Venkatasamy, Jie Gong
  • INTERLAYER FOR DEVICE INCLUDING NFT AND CLADDING LAYERS
    Publication number: 20150146508
    Abstract: A device that includes a near field transducer (NFT); at least one cladding layer adjacent the NFT; and a discontinuous metal layer positioned between the NFT and the at least one cladding layer.
    Type: Application
    Filed: January 28, 2015
    Publication date: May 28, 2015
    Inventors: Tong Zhao, Michael Christopher Kautzky, Michael Allen Seigler, Yongjun Zhao, Jay Jayashankar, Xiaoyue Huang
  • TMR device with novel free layer structure
    Patent number: 9040178
    Abstract: A TMR sensor that includes a free layer having at least one B-containing (BC) layer made of CoFeB, CoFeBM, CoB, COBM, or CoBLM, and a plurality of non-B containing (NBC) layers made of CoFe, CoFeM, or CoFeLM is disclosed where L and M are one of Ni, Ta, Ti, W, Zr, Hf, Tb, or Nb. One embodiment is represented by (NBC/BC)n where n?2. A second embodiment is represented by (NBC/BC)n/NBC where n?1. In every embodiment, a NBC layer contacts the tunnel barrier and NBC layers each with a thickness from 2 to 8 Angstroms are formed in alternating fashion with one or more BC layers each 10 to 80 Angstroms thick. Total free layer thickness is <100 Angstroms. The free layer configuration described herein enables a significant noise reduction (SNR enhancement) while realizing a high TMR ratio, low magnetostriction, low RA, and low Hc values.
    Type: Grant
    Filed: September 22, 2008
    Date of Patent: May 26, 2015
    Assignee: Headway Technologies, Inc.
    Inventors: Tong Zhao, Hui-Chuan Wang, Yu-Chen Zhou, Min Li, Kunliang Zhang
  • Reader fabrication method employing developable bottom anti-reflective coating
    Patent number: 9034564
    Abstract: Disclosed are methods for making read sensors using developable bottom anti-reflective coating and amorphous carbon (a-C) layers as junction milling masks. The methods described herein provide an excellent chemical mechanical polishing or planarization (CMP) stop, and improve control in reader critical physical parameters, shield to shield spacing (SSS) and free layer track width (FLTW).
    Type: Grant
    Filed: November 12, 2013
    Date of Patent: May 19, 2015
    Assignee: Western Digital (Fremont), LLC
    Inventors: Wei Gao, Miao Wang, Hai Sun, Ming Mao, Tong Zhao
  • METHODS OF FORMING NEAR FIELD TRANSDUCERS
    Publication number: 20150132503
    Abstract: Methods of forming a near field transducer (NFT), the method including depositing a plasmonic material; and laser annealing the plasmonic material.
    Type: Application
    Filed: November 13, 2014
    Publication date: May 14, 2015
    Inventors: Michael C. Kautzky, Tong Zhao, Sethuraman Jayashankar, Hui Brickner
  • NEAR FIELD TRANSDUCER HAVING SACRIFICIAL STRUCTURE
    Publication number: 20150131417
    Abstract: Near field transducers (NFTs) and devices that include a peg having an air bearing region and an opposing back region, the back region including a sacrificial structure, a disc having a first surface in contact with the peg, and a barrier structure, the barrier structure positioned between the opposing back region of the peg and the first surface of the disc.
    Type: Application
    Filed: November 7, 2014
    Publication date: May 14, 2015
    Inventors: Tong Zhao, Xiaoyue Huang, Michael C. Kautzky, Hui Brickner, Yi-Kuei Ryan Wu
  • Two step annealing process for TMR device with amorphous free layer
    Patent number: 9021685
    Abstract: An annealing process for a TMR or GMR sensor having an amorphous free layer is disclosed and employs at least two annealing steps. A first anneal at a temperature T1 of 200° C. to 270° C. and for a t1 of 0.5 to 15 hours is employed to develop the pinning in the AFM and pinned layers. A second anneal at a temperature T2 of 260° C. to 400° C. where T2>T1 and t1>t2 is used to crystallize the amorphous free layer and complete the pinning. An applied magnetic field of about 8000 Oe is used during both anneal steps. The mechanism for forming a sensor with high MR and robust pinning may involve structural change in the tunnel barrier or at an interface between two of the layers in the spin valve stack. A MgO tunnel barrier and a CoFe/CoB free layer are preferred.
    Type: Grant
    Filed: March 12, 2008
    Date of Patent: May 5, 2015
    Assignee: Headway Technologies, Inc.
    Inventors: Tong Zhao, Hui-Chuan Wang, Kunliang Zhang, Min Li
  • DEVICES INCLUDING NEAR FIELD TRANSDUCER AND ADHESION LAYERS
    Publication number: 20150117170
    Abstract: A device including a near field transducer (NFT); a write pole; at least one dielectric material positioned between the NFT and the write pole; and an adhesion layer positioned between the NFT and the at least one dielectric material.
    Type: Application
    Filed: April 25, 2013
    Publication date: April 30, 2015
    Inventors: Tong Zhao, Meng Zhu, Xiaoyue Huang, Michael C. Kautzky
  • MR device with synthetic free layer structure
    Patent number: 9013016
    Abstract: A magneto-resistive device having a large output signal as well as a high signal-to-noise ratio is described along with a process for forming it. This improved performance was accomplished by expanding the free layer into a multilayer laminate comprising at least three ferromagnetic layers separated from one another by antiparallel coupling layers. The ferromagnetic layer closest to the transition layer must include CoFeB while the furthermost layer is required to have low Hc as well as a low and negative lambda value. One possibility for the central ferromagnetic layer is NiFe but this is not mandatory.
    Type: Grant
    Filed: January 28, 2014
    Date of Patent: April 21, 2015
    Assignee: Headway Technologies, Inc.
    Inventors: Tong Zhao, Hui-Chaun Wang, Yu-Chen Zhou, Min Li, Kunliang Zhang
  • PROPULSION SYSTEM AND METHOD FOR DRIVING A VEHICLE
    Publication number: 20150102667
    Abstract: A propulsion system includes a traction drive system, a boost converter, an energy-type energy source, a power-type energy source, and an energy management system. The boost converter includes a high voltage side and a low voltage side. The boost converter is coupled to the traction drive system on the high voltage side. The energy-type energy source is coupled to the boost converter on the low voltage side thereof. The power-type energy source is coupled to the boost converter on the low voltage side thereof. The energy management system is coupled to the boost converter and configured to control the energy-type energy source and the power-type energy source through the boost converter in at least two conditions during a motoring mode.
    Type: Application
    Filed: October 10, 2014
    Publication date: April 16, 2015
    Inventors: Tong Zhao, Xi Lu, Ronghui Zhou, Fei Li
  • Devices including at least one intermixing layer
    Patent number: 8976634
    Abstract: Devices that include a near field transducer (NFT), the NFT including a peg having five exposed surfaces, the peg including a first material; an overlying structure; at least one intermixing layer, positioned between the peg and the overlying structure, the at least one intermixing layer positioned on at least one of the five surfaces of the peg, the intermixing layer including at least the first material and a second material.
    Type: Grant
    Filed: June 24, 2014
    Date of Patent: March 10, 2015
    Assignee: Seagate Technology LLC
    Inventors: Yuhang Cheng, Tong Zhao, Michael C. Kautzky, Ed F. Rejda, Kurt W. Wierman, Scott Franzen, Michael Allen Seigler
  • Devices including at least one adhesion layer and methods of forming adhesion layers
    Patent number: 8971161
    Abstract: Devices that include a near field transducer (NFT), the NFT having a disc and a peg, and the peg having five surfaces thereof; and at least one adhesion layer positioned on at least one of the five surfaces of the peg, the adhesion layer including one or more of the following: rhenium, osmium, iridium, platinum, hafnium, ruthenium, technetium, rhodium, palladium, beryllium, aluminum, manganese, indium, boron, and combinations thereof beryllium oxide, silicon oxide, iron oxide, zirconium oxide, manganese oxide, cadmium oxide, magnesium oxide, hafnium oxide, and combinations thereof tantalum carbide, uranium carbide, hafnium carbide, zirconium carbide, scandium carbide, manganese carbide, iron carbide, niobium carbide, technetium carbide, rhenium carbide, and combinations thereof chromium nitride, boron nitride, and combinations thereof.
    Type: Grant
    Filed: June 24, 2014
    Date of Patent: March 3, 2015
    Assignee: Seagate Technology LLC
    Inventors: Yuhang Cheng, Tong Zhao, Michael C. Kautzky, Ed F. Rejda, Kurt W. Wierman, Scott Franzen, Andrew J. Boyne, Michael Allen Seigler, Sethuraman Jayashankar
  • Semiconductor device and method of assembling same
    Patent number: 8969135
    Abstract: A semiconductor device includes a lead frame having a down bond area, a die attach area and a dam formed between the down bond area and the die attach area. A bottom of the dam is attached on a surface of the lead frame. The dam prevents contamination of the down bond area from die attach material, which may occur during a die attach process.
    Type: Grant
    Filed: November 11, 2013
    Date of Patent: March 3, 2015
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Peng Liu, Qingchun He, Zhaobin Qi, Liqiang Xu, Tong Zhao
  • Method and system for controlling motor
    Patent number: 8963460
    Abstract: A method for controlling a motor is provided. The method comprises obtaining electrical signals of the motor with a signal unit, the electrical signals comprising a motor torque and an angular velocity, calculating a voltage phase angle of a voltage vector with a calculating component, wherein a command torque, the motor torque, the angular velocity and a voltage amplitude of the voltage vector are inputs of the calculating component, and wherein the voltage phase angle is a variable and the voltage amplitude is a constant. The method further comprises modulating the voltage phase angle and the voltage amplitude to a switching signal for controlling an inverter; converting a direct current voltage to the voltage vector according to the switching signal, and applying the voltage vector to the motor.
    Type: Grant
    Filed: November 9, 2012
    Date of Patent: February 24, 2015
    Assignee: General Electric Company
    Inventors: Yong Li, Pengju Kang, Ronghui Zhou, Xiangming Shen, Xiao Chen, Zili Cai, Tong Zhao