Patents by Inventor Chul-Hwan Choi
Chul-Hwan Choi 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).
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Publication number: 20130025624Abstract: According to example embodiments, there is provided a method of cleaning a semiconductor device manufacturing apparatus. In the method, a fluorine-containing gas is provided into a chamber to clean a byproduct formed on a surface of a chamber during formation of a layer structure therein. A material is provided into the chamber to chemisorb the material on the surface of the chamber. The material is substantially similar to or the same as a source gas for forming the layer structure. A plasma is generated in the chamber, and the chamber is purged.Type: ApplicationFiled: July 11, 2012Publication date: January 31, 2013Inventors: Jeon-Ho Kim, Chul-Hwan Choi, Seung-Tae Lee, Yong-Gyu Lim, Kyung-Tae Kim, Jae-Min Kim
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Publication number: 20120279556Abstract: Provided are a photovoltaic apparatus and a manufacturing method thereof. The photovoltaic apparatus includes: substrate; a back electrode layer disposed on the substrate; a plurality of first intermediate layers disposed on the back electrode layer; a plurality of second intermediate layers disposed on the back electrode layer and each disposed between the first intermediate layers; light absorbing layers disposed on the first intermediate layers and the second intermediate layers; and a front electrode layer disposed on the light absorbing layer.Type: ApplicationFiled: October 7, 2010Publication date: November 8, 2012Applicant: LG INNOTEK CO., LTD.Inventor: Chul Hwan Choi
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Publication number: 20120198994Abstract: The present disclosure relates to an apparatus for controlling the angle of a swash plate of a hydraulic pump, and more particularly, to an apparatus for controlling the angle of a swash plate of a hydraulic pump in order to fix the swash plate at a desired angle by using an electric motor and an electromagnet. The apparatus for controlling the angle of a swash plate of a hydraulic pump includes a swash plate and a swash plate shaft coupled to the swash plate to be rotatable, and the apparatus further includes: an electric motor which directly connects the swash plate shaft or transmits a rotating force through a link connected to the swash plate shaft to pivot the swash plate; and an electromagnet which generates a magnetic force so that the swash plate moving according to the operation of the electric motor is fixed at a target angle.Type: ApplicationFiled: August 2, 2011Publication date: August 9, 2012Inventor: Chul Hwan CHOI
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Publication number: 20120174977Abstract: Provided are a solar cell apparatus and a method of manufacturing the same. The solar cell apparatus includes: a substrate; a back electrode layer on the substrate; an alloy layer on the back electrode layer; a light absorbing layer on the alloy layer; and a front electrode layer on the light absorbing layer.Type: ApplicationFiled: September 30, 2010Publication date: July 12, 2012Applicant: LG INNOTEK CO., LTD.Inventor: Chul Hwan Choi
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Publication number: 20120145530Abstract: There is provided a method for a purification of trichlorosilane, the method including: performing a pretreatment for separating a chlorosilane mixture from reaction products of a trichlorosilane production reaction; performing a first purification for separating the chlorosilane mixture into a first top stream and a first bottom stream; performing a second purification for separating the first top stream into a second top stream and a second bottom stream; and performing a third purification for separating the second bottom stream into a third top stream and a third bottom stream, wherein the performing of the third purification is carried out under pressure conditions higher than those of the performing of the second purification, and a heat exchange is generated between the second bottom stream and the third top stream.Type: ApplicationFiled: December 13, 2011Publication date: June 14, 2012Applicant: LG CHEM, LTD.Inventors: Chul-Hwan CHOI, Jeong-Seok LEE, Kwang-Wook CHOI, Joon-Ho SHIN, Dong-Kyu KIM
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Publication number: 20120037225Abstract: Disclosed are a solar cell and a method of fabricating the same. The solar cell includes a substrate, a rear electrode layer provided on the substrate, a light absorbing layer provided on the rear electrode layer, and a front electrode layer provided on the light absorbing layer, wherein the front electrode layer includes, a first conductive layer provided on the light absorbing layer, and a second conductive layer provided on the first conductive layer.Type: ApplicationFiled: June 16, 2010Publication date: February 16, 2012Applicant: LG INNOTEK CO., LTD.Inventors: Suk Jae Jee, Ho Gun Cho, Chul Hwan Choi
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Publication number: 20110259655Abstract: Provided is a tractor having a hydraulic lifting apparatus, wherein, assuming that a lift of the hydraulic lifting apparatus is P (N), a discharge flow rate of a hydraulic pump is Q (m3/s), a horsepower of an engine is H (N·m/s), an axial distance is L (m), and a total weight of the tractor is W (N), the following Equation is satisfied: 100×H/Q<P<L×W/1.5.Type: ApplicationFiled: March 29, 2011Publication date: October 27, 2011Inventors: Jung Woong CHOI, Chul Hwan CHOI
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Patent number: 7730807Abstract: A transmission for a tractor has a forward/reverse transmission unit for selectively changing a rotational direction of power of a first shaft connected with an engine and transmitting the power to a second shaft connected with an axle shaft, a main transmission unit installed between the second shaft and the axle shaft and having a plurality of gears to speed-change the power transmitted from the second shaft in four-speed, and a sub-transmission unit installed between the main transmission unit and the axle shaft and having a plurality of gears to speed-change again the power transmitted from the main transmission unit in four-speed. The transmission realizes forward/reverse 16-speed while having a compact structure.Type: GrantFiled: March 2, 2007Date of Patent: June 8, 2010Assignee: LS Mtron LtdInventors: Hyo-jung Kim, Chul-hwan Choi, Hyung-tai Kim, Jung-min Kim
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Publication number: 20070204708Abstract: A transmission for a tractor has a forward/reverse transmission unit for selectively changing a rotational direction of power of a first shaft connected with an engine and transmitting the power to a second shaft connected with an axle shaft, a main transmission unit installed between the second shaft and the axle shaft and having a plurality of gears to speed-change the power transmitted from the second shaft in four-speed, and a sub-transmission unit installed between the main transmission unit and the axle shaft and having a plurality of gears to speed-change again the power transmitted from the main transmission unit in four-speed. The transmission realizes forward/reverse 16-speed while having a compact structure.Type: ApplicationFiled: March 2, 2007Publication date: September 6, 2007Inventors: Hyo-jung Kim, Chul-hwan Choi, Hyung-tai Kim, Jung-min Kim
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Publication number: 20070193573Abstract: Semiconductor device manufacturing equipment has a vacuum system that enhances the fluency of the gas being discharged from a chamber of the equipment. The vacuum system has a vent line, and a throttle valve that includes a vent line opening and closing member oriented so that it is readily opened by a concentrated flow of gas in the vent line. The vacuum system may include a heating unit that heats the vent line through which the gas passes. Still further, a bend in the vent line upstream of the vent line opening and closing member may have a gently curved shape and/or may subtend an angle of less than 90°. As a result, the efficiency of the ventilation of the process chamber is improved, making it easier to control the pressure of the process chamber and minimizing the contamination of the throttle valve and the vent line.Type: ApplicationFiled: October 4, 2006Publication date: August 23, 2007Inventors: Kyung-Tae Kim, Chul-Hwan Choi, Kyung-Tae Kim, Jun-Woo Choi
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Patent number: 7202312Abstract: A method for preparing a cyclic olefin polymer is described. The method includes polymerizing cyclic olefin monomers or a cyclic olefin monomer with ethylene to prepare a cyclic olefin polymer solution; slowly adding a non-solvent drop wise to the cyclic olefin polymer solution to precipitate a cyclic olefin polymer; and filtering and drying the precipitated cyclic olefin polymer. In addition, the cyclic olefin polymer prepared using this method is described. According to the present invention, a spherical cyclic olefin polymer having a high bulk density can be easily separated from the cyclic olefin polymer solution by precipitation.Type: GrantFiled: January 27, 2005Date of Patent: April 10, 2007Assignee: LG Chem, Ltd.Inventors: Chul-Hwan Choi, Sung-Yeon Kim, Jung-Uk Choi
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Publication number: 20070072489Abstract: Semiconductor device manufacturing equipment is installed using a mock-up of the equipment. First, a full-scale layout drawing of the equipment is prepared. Also, a mock-up of the equipment is fabricated. The mock-up has wiring and pipe connectors of the same type as those of the main equipment. The layout drawing is placed on the floor of the site at which the main equipment is to be installed. Then the mock-up is placed at the same location where the main equipment is to be installed, as represented in the layout drawing, with the wiring and pipe connectors of the mock-up located at the same positions where the wiring and pipe connectors of the main equipment will be located. The wiring and piping of the semiconductor manufacturing equipment is installed, and ends of the wiring and piping are connected to the wiring and pipe connectors of the mock-up. Then the wiring and piping are inspected.Type: ApplicationFiled: April 13, 2006Publication date: March 29, 2007Inventors: Kyung-Tae Kim, Jun-Woo Choi, Chul-Hwan Choi
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Publication number: 20050171258Abstract: A method for preparing a cyclic olefin polymer is described. The method includes polymerizing cyclic olefin monomers or a cyclic olefin monomer with ethylene to prepare a cyclic olefin polymer solution; slowly adding a non-solvent drop wise to the cyclic olefin polymer solution to precipitate a cyclic olefin polymer; and filtering and drying the precipitated cyclic olefin polymer. In addition, the cyclic olefin polymer prepared using this method is described. According to the present invention, a spherical cyclic olefin polymer having a high bulk density can be easily separated from the cyclic olefin polymer solution by precipitation.Type: ApplicationFiled: January 27, 2005Publication date: August 4, 2005Inventors: Chul-Hwan Choi, Sung-Yeon Kim, Jung-Uk Choi
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Patent number: 6858062Abstract: A residual gas removing device for a gas supply apparatus in a semiconductor fabricating facility, includes a low stress valve disposed between a mass flow controller and a chamber. The low stress valve alternately supplies or cuts off a gas from the mass flow controller to the chamber. A WF6 gas removing apparatus is in flow communication with a gas inlet line of the low stress valve to remove a residual WF6 gas in the gas inlet line, before proceeding with a subsequent deposition step.Type: GrantFiled: January 16, 2002Date of Patent: February 22, 2005Assignee: Samsung Electronics Co., Ltd.Inventors: Chul-Hwan Choi, Jin-Ho Jeon, Yong-Gab Kim, Jong-Seung Yi, Min-Woo Lee, Kyung-Tae Kim, Chan-Hyung Cho
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Patent number: 6838645Abstract: A heater assembly that is capable of uniformly heating a wafer in an apparatus for manufacturing a semiconductor device is provided. The heater assembly preferably includes a susceptor configured to support a substrate (wafer). A plurality of heaters can be disposed under the susceptor to heat the wafer. A support is preferably disposed below the heaters to support the heaters, and a power supply provides an electric current to operate the heaters. The support can include a heat-shielding portion that restricts heat conduction between the heaters. The heat-shielding portion preferably comprises heat-resistant material arranged in a groove formed on the support. The heat-shielding portion also preferably supports adjacent peripheral portions of the heaters. Electrical current provided to the heaters is preferably controlled such that the temperature of the heaters are operated in a range of about 390° C. to 420° C.Type: GrantFiled: October 8, 2002Date of Patent: January 4, 2005Assignee: Samsung Electronics Co., Ltd.Inventors: Chul-Hwan Choi, Jin-Ho Jeon, Yong-Gab Kim, Sung-Hwan Jang, Dong-Won Lee, Min-Woo Lee, Kyung-Tae Kim
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Patent number: 6559316Abstract: This invention provides a method for preparing 2-(2-hydroxyphenyl)-2H-benzotriatzole of formula (I) below, consisting of steps of: a) performing a first reduction in which hydrazine hydrate is added to a compound of formula (II) below with or without a phase transition catalyst in the presence of solvents which include a nonpolar solvent, water, and an alkaline compound, thereby preparing a compound of formula (III) below; and b) performing a second reduction in which water is added to the compound of formula (III) prepared in step a), and then zinc powder and sulfuric acid are added thereto with or without the phase transition catalyst, wherein, X is halogen or hydrogen; R is hydrogen, C1-C12 alkyl, C5-C8 cycloalkyl, phenyl, or phelyl-C1-C4 alkyl; and R′ is C1-C12 alkyl, C5-C8 cycloalkyl, phenyl, or phenyl-C1-C4 alkyl.Type: GrantFiled: September 5, 2002Date of Patent: May 6, 2003Assignee: LG Chem, Ltd.Inventors: Jeong-Kyu Kim, Chul-Hwan Choi
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Publication number: 20030080109Abstract: A heater assembly that is capable of uniformly heating a wafer in an apparatus for manufacturing a semiconductor device is provided. The heater assembly preferably includes a susceptor configured to support a substrate (wafer). A plurality of heaters can be disposed under the susceptor to heat the wafer. A support is preferably disposed below the heaters to support the heaters, and a power supply provides an electric current to operate the heaters. The support can include a heat-shielding portion that restricts heat conduction between the heaters. The heat-shielding portion preferably comprises heat-resistant material arranged in a groove formed on the support. The heat-shielding portion also preferably supports adjacent peripheral portions of the heaters. Electrical current provided to the heaters is preferably controlled such that the temperature of the heaters are operated in a range of about 390° C. to 420° C.Type: ApplicationFiled: October 8, 2002Publication date: May 1, 2003Applicant: Samsung Electronics Co., Ltd.Inventors: Chul-Hwan Choi, Jin-Ho Jeon, Yong-Gab Kim, Sung-Hwan Jang, Dong-Won Lee, Min-Woo Lee, Kyung-Tae Kim
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Publication number: 20030050480Abstract: This invention provides a method for preparing 2-(2-hydroxyphenyl)-2H-benzotriazole of formula (I) below, consisting of steps of a) performing a first reduction in which hydrazine hydrate is added to a compound of formula (II) below with or without a phase transition catalyst in the presence of solvents which include a nonpolar solvent, water, and an alkaline compound, thereby preparing a compound of formula (III) below, and b) performing a second reduction in which water is added to the compound of formula (III) prepared in step a), and then zinc powder and sulfuric acid are added thereto with or without the phase transition catalyst, wherein, X is halogen or hydrogen, R is hydrogen, C1-C12 alkyl, C5-C8 cycloalkyl, phenyl, or phenyl-C1-C4 alkyl; and R′ is C1-C12 alkyl, C5-C8 cycloalkyl, phenyl, or phenyl-C1-C4 alkyl 1Type: ApplicationFiled: September 5, 2002Publication date: March 13, 2003Inventors: Jeong-Kyu KIM, Chul-Hwan Choi
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Publication number: 20020168251Abstract: Self-contained semiconductor device manufacturing equipment has a small floor area so that it can be installed in limited space in a production line, and is highly functional so as to enhance the productivity of the line. The equipment has a plurality of working chambers arrayed in at least a vertical direction, a transfer chamber to which the working chambers are independently connected, and a robot disposed in the transfer chamber for positioning a wafer relative to and transferring the wafer between respective ones the working chambers.Type: ApplicationFiled: January 18, 2002Publication date: November 14, 2002Inventors: Chul-Hwan Choi, Yong-Gab Kim, Chan-Hyung Cho
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Patent number: 6451694Abstract: In a process for mitigating and/or eliminating the abnormal growth of underlying polysilicon in dichloro silane-based CVD polycide WSix films, a first technique conducts the deposition of the underlying polysilicon layer at a temperature that substantially avoids crystallization of the underlying polysilicon. A second approach reduces the exposure (for example time period and or concentration) of the mono-silane SiH4 post flush, so as to avoid infusion of silicon into the underlying polysilicon layer, and resulting abnormal growth. In this manner, abnormal effects, such as stress fractures formed in subsequent layers, can be eliminated.Type: GrantFiled: April 4, 2001Date of Patent: September 17, 2002Assignee: Samsung Electronics Co., Ltd.Inventors: Jeon-Sig Lim, Jin-Ho Jeon, Jong-Seung Yi, Chul-Hwan Choi