Patents by Inventor Heon Chang

Heon Chang 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: 12001141
    Abstract: The present disclosure relates to a photopolymer composition, and more particularly, to a compound having a novel structure, a photopolymer composition including the compound as a dye, a hologram recording medium produced from the photopolymer composition, an optical element including the hologram recording medium, and a holographic recording method using the photopolymer composition.
    Type: Grant
    Filed: April 29, 2019
    Date of Patent: June 4, 2024
    Assignees: LG CHEM LTD., KOREA ADVANCED INSTITUTE OF SCIENCE AND TECHNOLOGY
    Inventors: Heon Kim, Yoosik Kim, Raisa Kharbash, Se Hyun Kwon, Yeongrae Chang, Seokhoon Jang
  • Patent number: 11994704
    Abstract: The present disclosure relates to a hologram recording medium having one surface with a higher surface energy than a polymer resin layer containing at least one polymer selected from the group consisting of triacetyl cellulose, alicyclic olefin polymer and polyethylene terephthalate, a hologram recording medium wherein the surface energy of any one surface is 50 mN/m or more, and an optical element comprising the hologram medium.
    Type: Grant
    Filed: September 11, 2019
    Date of Patent: May 28, 2024
    Assignee: LG CHEM, LTD.
    Inventors: Seokhoon Jang, Jinseok Byun, Heon Kim, Se Hyun Kwon, Yeongrae Chang
  • Patent number: 11945914
    Abstract: A curable composition for forming a high refractive index optical material including an episulfide compound, a cyclic disulfide compound, and a reducing agent, and an optical material comprising a cured product of the curable composition.
    Type: Grant
    Filed: May 19, 2020
    Date of Patent: April 2, 2024
    Assignee: LG CHEM, LTD.
    Inventors: Heon Kim, Hee Jung Choi, Yeongrae Chang
  • Publication number: 20070075304
    Abstract: A phase-change memory device more precisely controls electrical current required to accomplish a phase change by using contact holes that extend between phase change layers that are sized differently from each other.
    Type: Application
    Filed: May 24, 2006
    Publication date: April 5, 2007
    Inventors: Heon Chang, Suk Kyoung Hong, Hae Park
  • Publication number: 20060284159
    Abstract: A phase change memory device reduces the current necessary to cause a phase change of a phase change layer. The phase change memory device includes a first oxide layer formed on a semiconductor substrate; a lower electrode formed inside the first oxide layer; a second oxide layer formed on the first oxide layer including the lower electrode, the second oxide having a hole for exposing a part of the lower electrode; a phase change layer formed on a surface of the hole with a uniform thickness so as to make contact with the lower electrode; and an upper electrode formed in the hole and on a part of the second oxide layer, the part being adjacent to the hole.
    Type: Application
    Filed: June 2, 2006
    Publication date: December 21, 2006
    Inventors: Heon Chang, Suk Hong, Hae Park
  • Publication number: 20060278899
    Abstract: A phase change RAM device includes a semiconductor substrate having a phase change cell area and a voltage application area; a first oxide layer, a nitride layer and a second oxide layer sequentially formed on the semiconductor substrate; a first plug formed in the first oxide layer, the nitride layer and the second oxide layer of the phase change cell area; a second plug formed in the first oxide layer and the nitride layer of the voltage application area; a conductive line formed in the second oxide layer; a third oxide layer formed on the second oxide layer; a lower electrode shaped like a plug, the lower electrode being formed so as to directly make contact with the first plug; and a phase change layer and an upper electrode sequentially formed on the lower electrode in a pattern form.
    Type: Application
    Filed: June 2, 2006
    Publication date: December 14, 2006
    Inventors: Heon Chang, Suk Hong, Hae Park
  • Publication number: 20060278863
    Abstract: Disclosed are a phase change RAM device and a method for fabricating a phase change RAM device, which can efficiently lower intensity of current required for changing a phase of a phase change layer. The method includes the steps of providing a semiconductor substrate formed with an insulating interlayer including a tungsten plug, forming a first oxide layer on the semiconductor substrate, forming a pad-type bottom electrode, which makes contact with the tungsten plug, in the first oxide layer, forming a second oxide layer on the first oxide layer including the bottom electrode, and forming a porous polystyrene pattern on the second oxide layer such that a predetermined portion of the second oxide layer corresponding to a center portion of the bottom electrode is covered with the porous polystyrene pattern.
    Type: Application
    Filed: June 2, 2006
    Publication date: December 14, 2006
    Inventors: Heon Chang, Suk Hong, Hae Park
  • Publication number: 20060266991
    Abstract: Disclosed is a phase change memory device having a uniformly decreased writing current necessary for phase change of a phase change layer and a method for manufacturing the same. The phase change memory device includes a semiconductor substrate having a lower pattern; a first oxide layer formed on the semiconductor substrate to cover the lower pattern; a bottom electrode contact formed as a plug shape within the first oxide layer; a nano-size insulation layer formed on the first oxide layer including the bottom electrode contact; a phase change layer formed on the nano-size insulation layer; a top electrode formed on the phase change layer; a second oxide layer formed on the overall surface of the resulting substrate to cover a phase change cell having the bottom electrode contact, the nano-size insulation layer, the phase change layer, and the top electrode laminated successively; and a metal wiring formed within the second oxide layer to contact the top electrode.
    Type: Application
    Filed: October 11, 2005
    Publication date: November 30, 2006
    Inventors: Heon Chang, Suk Hong, Hae Park
  • Publication number: 20060003263
    Abstract: Disclosed are a phase-change memory device and its manufacturing method, which can reduce a contact area between a bottom electrode and a phase-change layer, thereby reducing the quantity of current necessary for phase change. The phase-change memory device comprises: a bottom electrode formed on a contact plug; a phase-change layer formed on the bottom electrode and having a shape of a character ‘?’; and a top electrode formed on the phase-change layer.
    Type: Application
    Filed: November 30, 2004
    Publication date: January 5, 2006
    Inventor: Heon Chang
  • Publication number: 20060003515
    Abstract: Disclosed are a phase-change memory device and its manufacturing method, which can reduce a contact area between a bottom electrode and a phase-change layer, thereby reducing the quantity of current necessary for phase change. The phase-change memory device comprises: bottom electrodes and top electrodes formed on a dielectric interlayer, each of the bottom electrodes and the top electrodes having both side surfaces in contact with a first oxide layer, a phase-change layer, a nitride layer, and a second oxide layer; the phase-change layer formed between the first oxide layer and the nitride layer while being in contact with the side surfaces of the bottom electrodes and the top electrodes; a third oxide layer formed on the bottom electrodes and the top electrode; and a metal wire in contact with the top electrode.
    Type: Application
    Filed: November 30, 2004
    Publication date: January 5, 2006
    Inventor: Heon Chang
  • Publication number: 20060003470
    Abstract: Disclosed are a phase-change random access memory device and a method for manufacturing the same, capable of improving a driving speed of the phase-change random access memory by reducing a contact surface between a bottom electrode and a phase-change layer. The phase-change random access memory device includes a first insulation layer formed on a semiconductor substrate and having a first contact hole for exposing a predetermined portion of the semiconductor substrate, a bottom electrode contact for filling the first contact hole, a first bottom electrode formed on the first insulation layer, a second bottom electrode spaced from the first bottom electrode by a predetermined distance, a second insulation layer formed on the first insulation layer, a phase-change layer pattern for filling the second contact hole, and a top electrode formed on the phase-change layer pattern.
    Type: Application
    Filed: November 30, 2004
    Publication date: January 5, 2006
    Inventor: Heon Chang
  • Publication number: 20060001164
    Abstract: Disclosed are a phase-change random access memory device and a method for manufacturing the same. The phase-change random access memory includes a first insulation layer having first contact holes, conductive plugs for filling the first contact holes, a second insulation layer having a second contact hole, and a bit line. Third and fourth insulation layers and a nitride layer are sequentially formed on the second insulation layer and have third contact holes. Bottom electrodes are provided to fill the third contact holes. An opening is formed in order to expose a part of the third insulation layer and a cavity is connected with the opening so as to expose a part of the bottom electrode. A phase-change layer pattern is connected to one side of the bottom electrode. A top electrode is formed on the phase-change layer pattern.
    Type: Application
    Filed: November 30, 2004
    Publication date: January 5, 2006
    Inventor: Heon Chang
  • Publication number: 20060001017
    Abstract: Disclosed are a phase-change random access memory device and a method for manufacturing the same by performing a photolithography process using electronic beam. The phase-change random access memory device includes a first insulation layer having first contact holes and a second contact hole, conductive plugs for filling the first contact holes, a bit line for filling the second contact hole, and a second insulation layer. A third insulation layer is formed on the second insulation layer. Third contact holes are formed in the third and second insulation layers. Fourth contact holes are formed between the hard mask layer and the third insulation layer. First and second bottom electrode contacts are provided to fill the third and fourth contact holes. Bottom electrodes are formed on the third insulation layer.
    Type: Application
    Filed: November 30, 2004
    Publication date: January 5, 2006
    Inventor: Heon Chang
  • Patent number: 5600201
    Abstract: An electron gun for a color cathode ray tube having a cathode, a control electrode and a screen electrode together constituting of a triode, and a main lens for focusing and accelerating an electron beam formed by the triode. The electron gun is characterized by a horizontally elongated electron beam passing hole formed in the control electrode having its long axis disposed in the arrangement direction of the electron beam passing hole. A horizontally elongated slot encompassing the electron beam passing hole having its long axis disposed in the arrangement direction of the electron beam passing hole is formed in the screen electrode opposed to the control electrode, thereby preventing the focusing characteristics of the electron beam from being reduced throughout the surface of the fluorescent layer by the influence of the deflection yoke.
    Type: Grant
    Filed: May 17, 1995
    Date of Patent: February 4, 1997
    Assignee: Samsung Display Devices Co., Ltd.
    Inventors: Neung-Yong Yun, Heon-Chang Kim, Han-Shin Do, Il-Tae Kim