Patents by Inventor Sok-hyun Kong

Sok-hyun Kong 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: 10026429
    Abstract: A perpendicular type of magnetic recording medium has a multi-layered recording structure made up of a plurality of ferro-magnetic layers and a non-magnetic layer interposed between the plurality of ferro-magnetic layers, and the perpendicular magnetic anisotropy energy of the lower ferro-magnetic layer is greater than the perpendicular magnetic anisotropy energy of the upper ferro-magnetic layer. Accordingly, the lower ferro-magnetic layer may be easily magnetically reversed by a magnetic field applied during a write operation. Thus, the perpendicular type of magnetic recording medium exhibits an enhanced thermal stability and write-ability.
    Type: Grant
    Filed: March 12, 2010
    Date of Patent: July 17, 2018
    Assignee: Seagate Technology LLC
    Inventors: Sok-hyun Kong, Hoo-san Lee, Sadayuki Watanabe, Shunji Takenoiri
  • Patent number: 8889274
    Abstract: An apparatus having a recording layer of a magnetic material with a concentration of implanted ions that increases in relation to a thickness direction of the recording layer to provide the recording layer with a continuously varied perpendicular magnetic anisotropy constant.
    Type: Grant
    Filed: January 28, 2013
    Date of Patent: November 18, 2014
    Assignee: Seagate Technology International
    Inventors: Seong-yong Yoon, Chee-kheng Lim, Hoo-san Lee, Hoon-sang Oh, Sok-hyun Kong
  • Patent number: 8441754
    Abstract: A servo master having a pattern capable of being magnetically transferred as a servo pattern to a magnetic recording medium, wherein the servo master is formed of a material having a magnetic anisotropic constant perpendicular to a surface of the magnetic recording medium. The magnetic transfer method can include preparing a servo master patterned with a servo pattern to be formed on a magnetic recording medium, and arranging the servo master on the magnetic recording medium and applying an external magnetic field to the servo master in a first direction perpendicular to a recording surface of the magnetic recording medium, and in a second direction parallel to the recording surface of the magnetic recording medium.
    Type: Grant
    Filed: June 16, 2009
    Date of Patent: May 14, 2013
    Assignee: Seagate Technology LLC
    Inventors: Hoo-san Lee, Sok-hyun Kong, Sung-chul Lee
  • Patent number: 8415035
    Abstract: A perpendicular magnetic recording medium is provided. The perpendicular magnetic recording medium includes: a perpendicular magnetic recording layer formed on a substrate; and at least one soft magnetic under-layer formed between the substrate and the perpendicular magnetic recording layer, wherein the soft magnetic under-layer is made from an alloy of a non-magnetic material and a magnetic material which exists in the form of granular nanoparticles in matrix of the non-magnetic material, and at least two of the magnetic nanoparticles are spaced apart from one another by a predetermined distance so as to mutually make an anti-ferromagnetic coupling.
    Type: Grant
    Filed: December 22, 2006
    Date of Patent: April 9, 2013
    Assignee: Seagate Technology LLC
    Inventors: Hoo San Lee, Hoon Sang Oh, Sok Hyun Kong, Seong Yong Yoon
  • Patent number: 8361641
    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: Grant
    Filed: January 23, 2008
    Date of Patent: January 29, 2013
    Assignee: Seagate Technology LLC
    Inventors: Seong-yong Yoon, Chee-kheng Lim, Hoo-san Lee, Hoon-sang Oh, Sok-hyun Kong
  • Patent number: 8021770
    Abstract: A perpendicular type of magnetic recording medium includes a substrate, a soft magnetic underlying section including a plurality of distinct layers soft magnetic material, a recording section, and an intermediate section upon which the recording section is formed. The intermediate section is provided to improve the crystal orientation and impart a desired magnetic characteristic to the recording section. An uppermost one of the layers of soft magnetic material which, of all of the layers of soft magnetic material, is disposed closest to the intermediate section is predisposed to induce the intermediate section to crystallize in a desired way as it is formed. Therefore, the intermediate section may have a minimal thickness and yet achieve a crystallization that is sufficient to control the forming of the recording section.
    Type: Grant
    Filed: March 12, 2010
    Date of Patent: September 20, 2011
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Sok-hyun Kong, Hoo-san Lee, Sadayuki Watanabe, Shunji Takenoiri
  • Patent number: 8007931
    Abstract: A perpendicular magnetic recording medium including: a substrate; a perpendicular magnetic recording layer disposed over the substrate; a soft magnetic underlayer disposed between the substrate and the perpendicular magnetic recording layer; a shunting layer disposed under the soft magnetic underlayer; and an isolation layer disposed between the soft magnetic underlayer and the shunting layer and providing magnetic isolation between the shunting layer and the other layers disposed over the shunting layer are provided. The shunting layer is magnetically separated from the other magnetic layers disposed over the shunting layer, and shunts a magnetic field generated by the magnetic domain walls of the soft magnetic underlayer such that the magnetic field cannot reach a magnetic head, thereby increasing a signal-to-noise ratio (SNR).
    Type: Grant
    Filed: January 26, 2007
    Date of Patent: August 30, 2011
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Hoo-san Lee, Chee-kheng Lim, Hoon-sang Oh, Sok-hyun Kong
  • Publication number: 20100233515
    Abstract: A perpendicular type of magnetic recording medium has a multi-layered recording structure made up of a plurality of ferro-magnetic layers and a non-magnetic layer interposed between the plurality of ferro-magnetic layers, and the perpendicular magnetic anisotropy energy of the lower ferro-magnetic layer is greater than the perpendicular magnetic anisotropy energy of the upper ferro-magnetic layer. Accordingly, the lower ferro-magnetic layer may be easily magnetically reversed by a magnetic field applied during a write operation. Thus, the perpendicular type of magnetic recording medium exhibits an enhanced thermal stability and write-ability.
    Type: Application
    Filed: March 12, 2010
    Publication date: September 16, 2010
    Applicants: SAMSUNG ELECTRONICS CO., LTD., FUJI ELECTRIC DEVICE TECHNOLOGY CO., LTD.
    Inventors: Sok-hyun Kong, Hoo-san Lee, Sadayuki Watanabe, Shunji Takenoiri
  • Publication number: 20100233516
    Abstract: A perpendicular type of magnetic recording medium includes a substrate, a soft magnetic underlying section including a plurality of distinct layers soft magnetic material, a recording section, and an intermediate section upon which the recording section is formed. The intermediate section is provided to improve the crystal orientation and impart a desired magnetic characteristic to the recording section. An uppermost one of the layers of soft magnetic material which, of all of the layers of soft magnetic material, is disposed closest to the intermediate section is predisposed to induce the intermediate section to crystallize in a desired way as it is formed. Therefore, the intermediate section may have a minimal thickness and yet achieve a crystallization that is sufficient to control the forming of the recording section.
    Type: Application
    Filed: March 12, 2010
    Publication date: September 16, 2010
    Applicants: SAMSUNG ELECTRONICS CO., LTD., FUJI ELECTRIC DEVICE TECHNOLOGY CO., LTD.
    Inventors: Sok-hyun Kong, Hoo-san Lee, Sadayuki Watanabe, Shunji Takenoiri
  • Publication number: 20090316297
    Abstract: A servo master having a pattern capable of being magnetically transferred as a servo pattern to a magnetic recording medium, wherein the servo master is formed of a material having a magnetic anisotropic constant perpendicular to a surface of the magnetic recording medium. The magnetic transfer method can include preparing a servo master patterned with a servo pattern to be formed on a magnetic recording medium, and arranging the servo master on the magnetic recording medium and applying an external magnetic field to the servo master in a first direction perpendicular to a recording surface of the magnetic recording medium, and in a second direction parallel to the recording surface of the magnetic recording medium.
    Type: Application
    Filed: June 16, 2009
    Publication date: December 24, 2009
    Applicant: Samsung Electronics Co., Ltd
    Inventors: Hoo-san LEE, Sok-hyun Kong, Sung-chul Lee
  • Publication number: 20090317663
    Abstract: Provided is a magnetic recording medium. The magnetic recording medium includes a substrate, a recording layer disposed on the substrate for magnetic recording, and a carbon protection layer, which includes a carbon layer and a blocking layer disposed in the carbon layer to block infiltration of external impurities, disposed on the recording layer. Since the blocking layer is disposed in the carbon layer, a thickness of the carbon protection layer can be reduced while a sufficient hardness to protect the recording layer can be ensured, and moreover, a softness of the surface of the carbon protection layer can be improved.
    Type: Application
    Filed: June 16, 2009
    Publication date: December 24, 2009
    Applicant: Samsung Electronics Co., Ltd
    Inventors: Sok-hyun KONG, Hyung-ik LEE, Hoo-san LEE, Young-su CHUNG, Seong-yong YOON
  • Publication number: 20090274933
    Abstract: Provided is a perpendicular magnetic recording medium. The perpendicular magnetic recording medium includes: a substrate; a soft magnetic layer disposed on the substrate; a recording layer disposed on the soft magnetic layer; and at least one hardness enhancing layer disposed in the soft magnetic layer or interposed between the soft magnetic layer and the recording layer.
    Type: Application
    Filed: November 25, 2008
    Publication date: November 5, 2009
    Applicant: SAMSUNG ELECTRONICS CO., LTD.
    Inventors: Seong-yong YOON, Hoo-san LEE, Sok-hyun KONG
  • Publication number: 20090197119
    Abstract: Provided is a perpendicular magnetic recording medium. The perpendicular magnetic recording medium includes: a substrate; a plurality of soft magnetic layers including a lower soft magnetic layer and an upper soft magnetic layer which are sequentially stacked on the substrate, wherein the upper soft magnetic layer has an anisotropic field greater than that of the lower soft magnetic layer; an isolating layer interposed between the lower and upper soft magnetic layers and preventing magnetic interaction between the lower and upper soft magnetic layers; an underlayer formed on the plurality of soft magnetic layers; and a recording layer formed on the underlayer and including a plurality of ferromagnetic layers each layer of which has a magnetic anisotropic energy which decreases as distance increases from the underlayer.
    Type: Application
    Filed: June 11, 2008
    Publication date: August 6, 2009
    Applicant: Samsung Electronics Co., Ltd.
    Inventors: Sok-hyun KONG, Seong-yong YOON, Hoo-san LEE
  • Publication number: 20090068500
    Abstract: Provided are a perpendicular magnetic recording medium and a method of manufacturing the same. The perpendicular magnetic recording medium includes: a substrate; a soft magnetic layer formed on the substrate; an underlayer formed on the soft magnetic layer; and a recording layer comprising a plurality of ferromagnetic layers and formed on the underlayer, wherein each of the plurality of ferromagnetic layers has a magnetic anisotropic energy which decreases as distance increases from the underlayer.
    Type: Application
    Filed: April 3, 2008
    Publication date: March 12, 2009
    Applicant: SAMSUNG ELECTRONICS CO., LTD.
    Inventors: Sok-hyun KONG, Sang-hwan PARK, Hoo-san LEE, Taek-dong LEE, Hoon-sang OH
  • 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: 20070298286
    Abstract: A perpendicular magnetic recording medium is provided. The perpendicular magnetic recording medium includes: a perpendicular magnetic recording layer formed on a substrate; and at least one soft magnetic under-layer formed between the substrate and the perpendicular magnetic recording layer, wherein the soft magnetic under-layer is made from an alloy of a non-magnetic material and a magnetic material which exists in the form of granular nanoparticles in matrix of the non-magnetic material, and at least two of the magnetic nanoparticles are spaced apart from one another by a predetermined distance so as to mutually make an anti-ferromagnetic coupling.
    Type: Application
    Filed: December 22, 2006
    Publication date: December 27, 2007
    Applicant: SAMSUNG ELECTRONICS CO., LTD.
    Inventors: Hoo San Lee, Hoon Sang Oh, Sok Hyun Kong, Seong Yong Yoon
  • Publication number: 20070230053
    Abstract: A magnetic recording medium is provided. The magnetic recording medium includes: a substrate; a perpendicular magnetic recording layer which is formed over the substrate; a first soft magnetic underlayer which is disposed between the perpendicular magnetic recording layer and the substrate; a second soft magnetic underlayer which is disposed between the first soft magnetic underlayer and the perpendicular magnetic recording layer; and an isolation layer which is disposed between the first soft magnetic underlayer and the second magnetic layer and which prevents magnetic interaction between the first soft magnetic underlayer and the second soft magnetic underlayer, wherein anisotropy field Hk of the second soft magnetic underlayer is greater than anisotropy field Hk of the first soft magnetic underlayer.
    Type: Application
    Filed: January 19, 2007
    Publication date: October 4, 2007
    Applicant: SAMSUNG ELECTRONICS CO., LTD.
    Inventors: Sok-hyun Kong, Chee-kheng Lim, Hoon-sang Oh, Hoo-san Lee, Seong-yong Yoon
  • Publication number: 20070212575
    Abstract: A perpendicular magnetic recording medium including: a substrate; a perpendicular magnetic recording layer disposed over the substrate; a soft magnetic underlayer disposed between the substrate and the perpendicular magnetic recording layer; a shunting layer disposed under the soft magnetic underlayer; and an isolation layer disposed between the soft magnetic underlayer and the shunting layer and providing magnetic isolation between the shunting layer and the other layers disposed over the shunting layer are provided. The shunting layer is magnetically separated from the other magnetic layers disposed over the shunting layer, and shunts a magnetic field generated by the magnetic domain walls of the soft magnetic underlayer such that the magnetic field cannot reach a magnetic head, thereby increasing a signal-to-noise ratio (SNR).
    Type: Application
    Filed: January 26, 2007
    Publication date: September 13, 2007
    Applicant: SAMSUNG ELECTRONICS CO., LTD.
    Inventors: Hoo-san Lee, Chee-kheng Lim, Hoon-sang Oh, Sok-hyun Kong