Patents by Inventor Chih-Huang Lai

Chih-Huang Lai 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: 20070253244
    Abstract: An apparatus and methods for a non-volatile magnetic random access memory (MRAM) device that includes a word line, a bit line, and a magnetic thin film memory element located at an intersection of the word and bit lines. The magnetic thin film memory element includes an alloy of a rare earth element and a transition metal element. The word line is operable to heat the magnetic thin film memory element when a heating current is applied. Heating of the magnetic thin film memory element to a predetermined temperature reduces its coercivity, which allows switching of the magnetic state upon application of a magnetic field. The magnetic state of the thin film element can be determined in accordance with principles of the Hall effect.
    Type: Application
    Filed: April 28, 2006
    Publication date: November 1, 2007
    Applicant: Taiwan Semiconductor Manufacturing Company, Ltd.
    Inventors: Chih-Huo Wu, Chih-Huang Lai, Yu-Jen Wang, Denny Tang
  • Publication number: 20070247756
    Abstract: A perpendicular magnetic recording medium includes: a substrate; a soft magnetic film formed on the substrate; a non-magnetic film including an amorphous interlayer formed on the soft magnetic film and made from a metallic material selected from terbium, gadolinium, dysprosium, tantalum, hafnium, and combinations thereof, a buffer layer formed on the amorphous interlayer and having a face-centered cubic structure, and a seed layer formed on the buffer layer and having a hexagonal crystal structure; and a granular magnetic recording film formed on the seed layer.
    Type: Application
    Filed: October 30, 2006
    Publication date: October 25, 2007
    Inventors: Chih-Huang Lai, David Vokoun, Yu-Yi Liao, Meng-Shian Lin
  • Publication number: 20070166839
    Abstract: A fabrication method of a magnetoresistance multi-layer is provided. The method includes forming a multi-layer with at least an antiferromagnetic layer and performing an ion irradiation process to the multi-layer to transform a disordered structure of the antiferromagnetic layer to an ordered structure. Accordingly, the process time can be reduced and the interdiffusion in the multi-layer can be prevented.
    Type: Application
    Filed: May 12, 2006
    Publication date: July 19, 2007
    Inventors: Chih-Huang Lai, Sheng-Huang Huang, Cheng-Han Yang, Yung-Hung Wang, Wei-Chuan Chen, Kuei-Hung Shen
  • Publication number: 20060238925
    Abstract: Disclosed herein is a magnetoresistive structure, for example useful as a spin-valve or GMR stack in a magnetic sensor, and a fabrication method thereof. The magnetoresistive structure uses twisted coupling to induce a perpendicular magnetization alignment between the free layer and the pinned layer. Ferromagnetic layers of the free and pinned layers are exchange-coupled using antiferromagnetic layers having substantially parallel exchange-biasing directions. Thus, embodiments can be realized that have antiferromagnetic layers formed of a same material and/or having a same blocking temperature. At least one of the free and pinned layers further includes a second ferromagnetic layer and an insulating layer, such as a NOL, between the two ferromagnetic layers. The insulating layer causes twisted coupling between the two ferromagnetic layers, rotating the magnetization direction of one 90 degrees relative to the magnetization direction of the other.
    Type: Application
    Filed: April 22, 2005
    Publication date: October 26, 2006
    Applicant: TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY, LTD.
    Inventors: Yu-Jen Wang, Chih-Huang Lai, Wen-Chin Lin, Denny Tang, Chao-Hsiung Wang
  • Publication number: 20060233002
    Abstract: A memory cell structure. A first conductive line is cladded by at least two first ferromagnetic layers respectively having a first easy axis and a second easy axis, a nano oxide layer located between the first ferromagnetic layers, and a first pinned ferromagnetic layer. The first and second easy axes are 90 degree twisted-coupled with the first easy axis parallel to the length of the first conductive line and the second easy axis perpendicular to the length of the first conductive line. A storage device is adjacent to the first conductive line, receiving a magnetic field generated from a current flowing through the first conductive line.
    Type: Application
    Filed: March 30, 2005
    Publication date: October 19, 2006
    Inventors: Yu-Jen Wang, Chih-Huang Lai, Denny Tang, Wen Lin
  • Publication number: 20040075958
    Abstract: A magnetoresistive (MR) device includes a synthetic antiferromagnetic (AFM) layer having an Fe/FeSi/Fe construction. A first Fe layer of the synthetic AFM layer has a magnetization substantially in a first direction, while a second Fe layer of the synthetic AFM layer has a magnetization substantially in a second direction that is substantially antiparallel to the first direction. The magnetoresistive device can be a spin valve in which a first surface of the synthetic AFM layer is adjacent to a pinning layer, and a second surface of the synthetic AFM layer is adjacent to a spacer layer. Further, the spin valve includes a free layer that overlies the spacer, thereby being separated from the synthetic AFM layer by the spacer. The pinning layer, synthetic AFM layer, spacer, and free layer can be bounded by a first shield and a second shield to provide magnetic shielding of the spin valve sensor.
    Type: Application
    Filed: October 14, 2003
    Publication date: April 22, 2004
    Applicant: Western Digital (Fremont)
    Inventors: Chih-Huang Lai, Zhupei Shi, Hua-Ching Tong, Robert E. Rottmayer, Charles W. Miller
  • Patent number: 6633464
    Abstract: A magnetoresistive (MR) device includes a synthetic antiferromagnetic (AFM) layer having an Fe/FeSi/Fe construction. A first Fe layer of the synthetic AFM layer has a magnetization substantially in a first direction, while a second Fe layer of the synthetic AFM layer has a magnetization substantially in a second direction that is substantially antiparallel to the first direction. The magnetoresistive device can be a spin valve in which a first surface of the synthetic AFM layer is adjacent to a pinning layer, and a second surface of the synthetic AFM layer is adjacent to a spacer layer. Further, the spin valve includes a free layer that overlies the spacer, thereby being separated from the synthetic AFM layer by the spacer. The pinning layer, synthetic AFM layer, spacer, and free layer can be bounded by a first shield and a second shield to provide magnetic shielding of the spin valve sensor.
    Type: Grant
    Filed: December 9, 1998
    Date of Patent: October 14, 2003
    Assignee: Read-Rite Corporation
    Inventors: Chih-Huang Lai, Zhupei Shi, Hua-Ching Tong, Robert E. Rottmayer, Charles W. Miller
  • Patent number: 6417999
    Abstract: In at least one embodiment, the method of the present invention is embodied in a method for fabricating a magnetoresistive head structure which includes obtaining a lead and magnetic bias layer, applying a photoresist layer over the lead and magnetic bias layer and about a desired position of a sensor such that the desired position of the sensor is substantially free of the photoresist layer, etching the lead and magnetic bias material substantially at the desired position of the sensor, depositing a sensor at the desired position of the sensor; and removing the photoresist. Obtaining the lead and magnetic bias layers can be done by depositing them.
    Type: Grant
    Filed: February 4, 2000
    Date of Patent: July 9, 2002
    Assignee: Read-Rite Corporation
    Inventors: Kenneth E. Knapp, Ronald A. Barr, Chih-Huang Lai, Robert Rottmayer
  • Patent number: 6330136
    Abstract: An Spin Dependent Tumelina SDT read sensor includes a first ferromagnetic (FM) layer and a second FM layer separated by an insulating layer. The first FM layer and second FM layer are substantially electrically isolated from each other. Specifically, the sidewalls of the SDT read sensor are substantially free of electrical paths between the first FM layer and the second FM layer. Also, a surface of the second FM layer that is substantially parallel to the air bearing surface, is recessed from the air bearing surface. A method for forming an SDT read sensor includes depositing a first FM material layer, depositing an intermediate insulation material layer over the first FM material layer, and then depositing a second FM material layer over the intermediate insulation material layer. The second FM material layer and the intermediate insulation material layer are etched, with the etching being stopped before the etching etches the first FM material layer.
    Type: Grant
    Filed: October 14, 1998
    Date of Patent: December 11, 2001
    Assignee: Read-Rite Corporation
    Inventors: Lien-Chang Wang, Chih-Huang Lai, Tai Min, Zhupei Shi, Billy W. Crue, Jr.
  • Publication number: 20010012187
    Abstract: A magnetoresistive (MR) device includes a synthetic antiferromagnetic (AFM) layer having an Fe/FeSi/Fe construction. A first Fe layer of the synthetic AFM layer has a magnetization substantially in a first direction, while a second Fe layer of the synthetic AFM layer has a magnetization substantially in a second direction that is substantially antiparallel to the first direction. The magnetoresistive device can be a spin valve in which a first surface of the synthetic AFM layer is adjacent to a pinning layer, and a second surface of the synthetic AFM layer is adjacent to a spacer layer. Further, the spin valve includes a free layer that overlies the spacer, thereby being separated from the synthetic AFM layer by the spacer. The pinning layer, synthetic AFM layer, spacer, and free layer can be bounded by a first shield and a second shield to provide magnetic shielding of the spin valve sensor.
    Type: Application
    Filed: December 9, 1998
    Publication date: August 9, 2001
    Inventors: CHIH-HUANG LAI, ZHUPEI SHI, HUA-CHING TONG, ROBERT E. ROTTMAYER, CHARLES W. MILLER
  • Patent number: 6185077
    Abstract: A stable pinned structure for a magnetoresistive sensor includes a pair of ferromagnetic layers sandwiched about an antiferromagnetic layer, the ferromagnetic layers having substantially opposite magnetic directions magnetostatically coupled and pinned by the antiferromagnetic layer. A free layer of ferromagnetic material has a magnetic direction that can rotate in the presence of an applied magnetic field so that the field can be sensed. A second free layer may be provided, such that the free layers are sandwiched about the pinned structure, with the sensor configured for amplifying signals and minimizing common mode noise.
    Type: Grant
    Filed: January 6, 1999
    Date of Patent: February 6, 2001
    Assignee: Read-Rite Corporation
    Inventors: Hua-Ching Tong, Tai Min, Jian-Gang Zhu, Chih-Huang Lai