Patents by Inventor Chee-kheng Lim

Chee-kheng Lim 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: 7672081
    Abstract: A perpendicular magnetic recording head which moves in a track direction of a recording layer of a perpendicular magnetic recording medium to write information on the recording layer or read information from the recording layer. The perpendicular magnetic recording head includes: the perpendicular magnetic recording medium including a soft magnetic underlayer and the recording layer; a write head including a main pole that applies a magnetic field to, and writes information to, the recording layer and a return pole having a first end which is connected to the main pole and having a second end which is spaced apart from the main pole over an air bearing surface (ABS) of the perpendicular magnetic recording head which is adjacent to the recording layer; and a permanent magnet formed on at least one side of the write head.
    Type: Grant
    Filed: August 14, 2006
    Date of Patent: March 2, 2010
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Chee-kheng Lim, Eun-sik Kim, Yong-su Kim
  • Patent number: 7652906
    Abstract: Provided is a memory device employing magnetic domain wall movement. The memory device includes a first track, an interconnecting layer, and a second track. The first track including a magnetic material is formed in a first direction. The interconnecting layer is formed on the first track. The second track including a magnetic material is formed in a second direction on the interconnecting layer.
    Type: Grant
    Filed: September 6, 2007
    Date of Patent: January 26, 2010
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Chee-kheng Lim, Eun-sik Kim, Sung-chul Lee
  • Patent number: 7639454
    Abstract: A perpendicular magnetic recording head includes: a main pole; a return pole spaced a predetermined gap from the main pole; an induction coil inducing a magnetic field on the main pole; and two or more gap shields, wherein the two or more gap shields are formed in the gap between the main pole and the return pole.
    Type: Grant
    Filed: July 27, 2006
    Date of Patent: December 29, 2009
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Chee-kheng Lim, Eun-sik Kim, Yong-su Kim, Young-hun Im
  • Patent number: 7601443
    Abstract: A recording medium including a perpendicular magnetic recording layer and a laminated SUL formed on a substrate is provided. The SUL includes an antiferromagnetic layer interposed between laminated structures including a magnetic layer, a non-magnetic layer and a magnetic layer. The layers may each have a thickness of 20 nm or less and the layers below the antiferromagnetic layer may be thinner than the layers on the antiferromagnetic layer. The laminated structures formed on and below the antiferromagnetic layer have unidirectional magnetic anisotropies set in the opposite radial direction to each other by an exchange bias. As a result, media magnetic domain noise can be diminished.
    Type: Grant
    Filed: October 27, 2005
    Date of Patent: October 13, 2009
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Chee-kheng Lim, Yong-su Kim, Byung-kyu Lee, Hoon-sang Oh, Tae-hyo Lee
  • Publication number: 20090201720
    Abstract: A multi-bit magnetic random access memory device and a method for writing to and sensing the multi-bit magnetic random access memory device. The magnetic memory includes a memory cell with a multilayer structure having a plurality of data layers which can each store one bit. The structure includes a plurality of magnetically changeable ferromagnetic layers, a ferromagnetic reference layer having a fixed magnetization state, a first spacer layer separating the magnetically changeable ferromagnetic layers, and a second spacer layer separating the ferromagnetic reference layer from the magnetically changeable ferromagnetic layers. This structure allows for more than one-bit to be stored as well as for efficient writing and reduced power consumption.
    Type: Application
    Filed: February 2, 2009
    Publication date: August 13, 2009
    Applicant: SAMSUNG ELECTRONICS CO., LTD.
    Inventor: Chee-kheng LIM
  • Patent number: 7567453
    Abstract: An advanced multi-bit magnetic random access memory device and a method for writing to the advanced multi-bit magnetic random access memory device. The magnetic memory includes one or more pair-cells. A pair-cell is two memory cells. Each memory cell has a magnetic multilayer structure. The structure includes a magnetically changeable ferromagnetic layer, a ferromagnetic reference layer having a non-changeable magnetization state, and a corresponding spacer layer separating the ferromagnetic layers. The memory cells are arranged such that an effective remnant magnetization of each of the cells is non-parallel from the cells' long-axis. This allows for more than one-bit to be stored as well as for efficient writing and reduced power consumption.
    Type: Grant
    Filed: January 9, 2008
    Date of Patent: July 28, 2009
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Chee-kheng Lim
  • Patent number: 7502248
    Abstract: A multi-bit magnetic random access memory device and a method for writing to and sensing the multi-bit magnetic random access memory device. The magnetic memory includes a memory cell with a multilayer structure having a plurality of data layers which can each store one bit. The structure includes a plurality of magnetically changeable ferromagnetic layers, a ferromagnetic reference layer having a fixed magnetization state, a first spacer layer separating the magnetically changeable ferromagnetic layers, and a second spacer layer separating the ferromagnetic reference layer from the magnetically changeable ferromagnetic layers. This structure allows for more than one-bit to be stored as well as for efficient writing and reduced power consumption.
    Type: Grant
    Filed: April 29, 2005
    Date of Patent: March 10, 2009
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Chee-kheng Lim
  • Patent number: 7486478
    Abstract: Provided is a magnetic head having a magnetic thin film structure that reduces the effect of a stray field and generates a magnetization reversal at a high speed. The magnetic head includes a first pole, a second pole spaced apart from the first pole, and an induction coil that induces a magnetic field in the first and second poles, wherein the first and second poles include a pole tip in which a leakage flux for recording is generated, and a head yoke that guides the flux flowing in the poles, and at least one implant for controlling a magnetic domain, the implant formed in at least one of the first and second poles. The magnetic thin film can effectively reduce the effect of a stray field entering from the outside, and can control a domain wall motion so that high speed magnetic recording is possible, by generating a magnetization reversal at a high speed corresponding to a magnetic field applied by an induction coil.
    Type: Grant
    Filed: October 12, 2005
    Date of Patent: February 3, 2009
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Chee-kheng Lim, Yong-su Kim
  • Publication number: 20080299416
    Abstract: A perpendicular magnetic recording medium and a method of manufacturing the same are provided. The perpendicular magnetic recording medium comprises a recording layer including a plurality of regions formed in the depth direction of the recording layer and a magnetic anisotropy constant of a region relatively deeper than another region, among the plurality of regions, is greater than that of the another region. The method of manufacturing a perpendicular magnetic recording medium includes: forming a recording layer having perpendicular magnetic anisotropy; and irradiating the recording layer with ions.
    Type: Application
    Filed: January 23, 2008
    Publication date: December 4, 2008
    Applicant: Samsung Electronics Co., Ltd.
    Inventors: Seong-yong YOON, Chee-kheng Lim, Hoo-san Lee, Hoon-sang Oh, Sok-hyun Kong
  • Publication number: 20080158710
    Abstract: In an information storage device, a writing magnetic layer is formed on a substrate and has a magnetic domain wall. A connecting magnetic layer is formed on the writing magnetic layer, and an information storing magnetic layer is formed on an upper portion of side surfaces of the connecting magnetic layer. A reader reads information stored in the information storing magnetic layer.
    Type: Application
    Filed: October 31, 2007
    Publication date: July 3, 2008
    Inventor: Chee-kheng Lim
  • Publication number: 20080160349
    Abstract: Example embodiments may provide data storage devices using movement of magnetic domain walls including a first magnetic layer having at least two magnetic domains with determinable magnetization directions, and/or a soft second magnetic layer formed on a lower surface of the first magnetic layer. Magnetic domain walls may be moved even in curved regions of the first magnetic layer.
    Type: Application
    Filed: December 11, 2007
    Publication date: July 3, 2008
    Inventor: Chee-kheng Lim
  • Publication number: 20080158707
    Abstract: An information storage device includes a record head and a data recording medium. The record head includes a magnetic substance having magnetic domain walls and records data in the data recording medium. In a method of operating the information storage device, a first high frequency current or a high frequency magnetic field is supplied to the magnetic substance while magnetic domain walls of the magnetic substance are moved.
    Type: Application
    Filed: October 31, 2007
    Publication date: July 3, 2008
    Inventors: Hoo-san Lee, Chee-kheng Lim, Hoon-sang Oh
  • Publication number: 20080152953
    Abstract: An information storage device includes a magnetic layer and a supply unit. The magnetic layer includes a plurality of regions, a first region having a first magnetic anisotropic energy and a second region having a second magnetic anisotropic energy. The first and second regions are arranged alternately, and the second region is doped with impurity ions. The second magnetic anisotropic energy is less than the first magnetic anisotropic energy. The supply unit applies energy to the magnetic layer for moving magnetic domain walls within the magnetic layer.
    Type: Application
    Filed: October 31, 2007
    Publication date: June 26, 2008
    Inventor: Chee-kheng Lim
  • Publication number: 20080152794
    Abstract: An information storage device using movement of magnetic domain walls includes a writing magnetic layer having a magnetic domain wall. A stack structure is formed on the writing magnetic layer. The stack structure includes a connecting magnetic layer and an information storing magnetic layer stacked sequentially. The information storage device also includes a reader for reading information stored in the information storing magnetic layer.
    Type: Application
    Filed: October 31, 2007
    Publication date: June 26, 2008
    Inventors: Chee-kheng Lim, Eun-hyoung Cho, Sung-hoon Choa
  • Publication number: 20080152954
    Abstract: An information storage device includes a writing magnetic layer including a magnetic domain wall. An information storing magnetic layer is connected to the writing magnetic layer, and includes at least one magnetic domain wall. The information storage device also includes a reader for reading data recorded in the information storing magnetic layer. The connection layer includes a first portion with a first width adjacent to the writing magnetic layer and a second portion with a second width adjacent to the at least one information storing magnetic layer. The first width is less than the second width.
    Type: Application
    Filed: October 31, 2007
    Publication date: June 26, 2008
    Inventor: Chee-Kheng Lim
  • Publication number: 20080144217
    Abstract: Provided are a patterned magnetic recording medium and a method of manufacturing the same. The patterned magnetic recording medium include: a substrate; and a plurality of magnetic recording layers arranged at predetermined intervals, wherein the magnetic recording layers are formed of an alloy including Co, Pt, and Ni. The patterned medium having the magnetic recording layers have an excellent read/write characteristic and high corrosion resistance and recording density.
    Type: Application
    Filed: September 26, 2007
    Publication date: June 19, 2008
    Applicant: Samsung Electronics Co., Ltd.
    Inventors: Myung-bok LEE, Jin-seung Sohn, Chee-kheng Lim
  • Publication number: 20080138659
    Abstract: Example embodiments may provide data storage devices using movement of a magnetic domain wall and/or a method of operating magnetic domain data storage devices. The data storage device may include a first magnetic layer for writing data having two magnetic domains magnetized in different directions, a second magnetic layer for storing data at a side of the first magnetic layer, a data recording device connected to the first magnetic layer and the second magnetic layer, and a plurality of reading heads configured to read the second magnetic layer. The data storage device may store a larger amount of data without requiring moving mechanical systems.
    Type: Application
    Filed: October 31, 2007
    Publication date: June 12, 2008
    Inventors: Chee-kheng Lim, In-kyeong Yoo, Sung-hoon Choa
  • Publication number: 20080137406
    Abstract: Example embodiments may provide magnetic domain information storage devices with trenches and a method of manufacturing the information storage device. Example embodiment information storage devices may include a magnetic layer on a substrate having a plurality of magnetic domains and a power unit for moving magnetic domain walls. Magnetic layers may be parallel to the substrate, and a plurality of trenches in the magnetic layer may be perpendicular to the substrate. Portions of a lower surface of the magnetic layer corresponding to trenches may protrude downward.
    Type: Application
    Filed: December 6, 2007
    Publication date: June 12, 2008
    Inventors: Chee-kheng Lim, Sung-hoon Choa
  • Publication number: 20080137231
    Abstract: Provided are a magnetic recording medium and a method of fabricating the same. The magnetic recording medium includes a substrate; and a recording layer, wherein the recording layer is formed of a plurality of magnetic dots, and a non-magnetic region that is formed on the substrate to isolate each of the magnetic dot.
    Type: Application
    Filed: June 6, 2007
    Publication date: June 12, 2008
    Applicant: SAMSUNG ELECTRONICS CO., LTD.
    Inventors: Chee-kheng LIM, Jin-seung SOHN, Byun-kyu LEE, Eun-hyoung CHO, Hae-sung KIM
  • Publication number: 20080138661
    Abstract: Provided are an information storage device using movement of a magnetic domain wall, and methods of manufacturing and operating the information storage device. The information storage device includes a storage track having magnetic domains and a writer for recording data to the storage track, wherein the writer comprises: a first magnetic layer and a second magnetic layer that is formed to cover a portion of the first magnetic layer and has a smaller magnetic anisotropic energy than the first magnetic layer.
    Type: Application
    Filed: July 23, 2007
    Publication date: June 12, 2008
    Applicant: Samsung Electronics Co., Ltd.
    Inventors: Chee-kheng LIM, Sung-hoon Choa