Patents by Inventor Joo Won Choi
Joo Won 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: 20240128915Abstract: Disclosed is a motor driving apparatus including: a motor; an inverter including a switching element for driving the motor; a controller for controlling the switching element; a resolver including an excitation winding and a detection winding; and a resolver chip applying an excitation signal to the excitation winding by inputting a periodic signal from the controller, and receiving a feedback signal from the detection winding, wherein the resolver chip determines the number of rotations of the motor based on a change in a pulse width of a detection signal resulting from a comparison between a voltage of the feedback signal and a preset voltage, and output a signal to the inverter for setting an inertial driving control mode according to the number of rotations of the motor in a failure state of the controller.Type: ApplicationFiled: October 17, 2023Publication date: April 18, 2024Applicant: HYUNDAI MOBIS CO., LTD.Inventors: Tae Hwan KANG, Hyung Min PARK, Joo Won PARK, Beom Cheol CHO, Yun Ho CHOI, Yeon Ho KIM, Won Hee JO
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Publication number: 20240069524Abstract: Disclosed is an apparatus for excitation signal generation for a resolver. The apparatus includes a sine wave generator that generates a sine wave based on a square wave, an amplifier that amplifies the sine wave, a differential signal generator that converts, into a differential signal, the amplified sine wave, a driver that inputs the differential signal to a coil, and a processor that generates an excitation signal by increasing a voltage of the sine wave from a start voltage to a target voltage through at least one of the sine wave generator and the amplifier based on a transient current that flows into the coil in a transient response interval.Type: ApplicationFiled: December 27, 2022Publication date: February 29, 2024Applicant: HYUNDAI MOBIS CO., LTD.Inventors: Yun Ho CHOI, Hyung Min PARK, Joo Won PARK, Yeon Ho KIM, Won Hee JO, Tae Hwan KANG, Beom Cheol CHO
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Patent number: 11488844Abstract: Disclosed is a first cleaning apparatus including a first cleaning bath, a cover provided at the upper part of the first cleaning bath, a drainage portion provided at the lower part of the first cleaning bath, a first cleaning unit and a second cleaning unit provided respectively at a first side surface and a second side surface in the first cleaning bath, and first and second moving units configured to move the first and second cleaning units, respectively, wherein each of the first and second cleaning units includes a plurality of cleaning solution supply pipes provided at different heights and a plurality of nozzles provided at each of the cleaning solution supply pipes, the nozzles provided at one cleaning solution supply pipe have identical cleaning solution spray angles, and the nozzles provided at the other cleaning solution supply pipes have different cleaning solution spray angles.Type: GrantFiled: January 11, 2021Date of Patent: November 1, 2022Assignee: SK Siltron Co., Ltd.Inventors: Ki Soo Kwon, Joo Won Choi
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Publication number: 20210242041Abstract: Disclosed is a first cleaning apparatus including a first cleaning bath, a cover provided at the upper part of the first cleaning bath, a drainage portion provided at the lower part of the first cleaning bath, a first cleaning unit and a second cleaning unit provided respectively at a first side surface and a second side surface in the first cleaning bath, and first and second moving units configured to move the first and second cleaning units, respectively, wherein each of the first and second cleaning units includes a plurality of cleaning solution supply pipes provided at different heights and a plurality of nozzles provided at each of the cleaning solution supply pipes, the nozzles provided at one cleaning solution supply pipe have identical cleaning solution spray angles, and the nozzles provided at the other cleaning solution supply pipes have different cleaning solution spray angles.Type: ApplicationFiled: January 11, 2021Publication date: August 5, 2021Inventors: Ki Soo KWON, Joo Won CHOI
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Publication number: 20200295239Abstract: Aspects of the disclosure provide for light conversion devices incorporating quantum dots and methods of fabricating the same. In accordance with some embodiments of the present disclosure, a light conversion device is provided. The light conversion device may include. a porous structure comprising one or more nanoporous materials, wherein the one or more nanoporous materials comprise a plurality of pores; and a plurality of quantum dots placed in the porous structure, wherein the plurality of quantum dots comprises a first plurality of quantum dots configured to convert light of a first color into light of a second color, and a second plurality of quantum dots configured to convert the light of the first color into light of a third color. Each of the plurality of pores may have a nanoscale size. The nonporous materials may further include a matrix comprising a semiconductor material, glass, plastic, metal, polymer, etc.Type: ApplicationFiled: March 11, 2020Publication date: September 17, 2020Inventors: Jie Song, Joo Won Choi, Chen Chen
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Publication number: 20200194619Abstract: In accordance with some embodiments of the present disclosure, a semiconductor device (e.g., a light-emitting device) is provided. The semiconductor device may include a first epitaxial layer of a first group III-V material, a superlattice layer grown on the first epitaxial layer of the first group III-V material, and a second epitaxial layer of the first group iii-v material grown on the superlattice layer. In some embodiments, the superlattice layer may include the first group III-V material and a second group III-V material. In some embodiments, the first epitaxial layer may include the first group III-V material of a semipolar orientation. The semipolar orientation may include at least one of at least one of a (2021) orientation, a (2021) orientation, a (3031) orientation, or a (3031) orientation including off-axis orientations within ±4 degrees. The second epitaxial layer may include the first group III-V material of the semipolar orientation.Type: ApplicationFiled: December 13, 2019Publication date: June 18, 2020Inventors: Joo Won Choi, Jie Song, Chen Chen
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Patent number: 10672948Abstract: Aspects of the disclosure provide for mechanisms for fabricating light extraction structures for semiconductor devices (e.g., light-emitting devices). In accordance with some embodiments, a semiconductor device is provided. The semiconductor device may include: a first semiconductor layer including an epitaxial layer of a semiconductor material; a second semiconductor layer comprising an active layer; and a light-reflection layer configured to cause at least a portion of light produced by the active layer to emerge from the semiconductor device via a surface of the second semiconductor layer, wherein the light-reflection layer is positioned between the first semiconductor layer and the second semiconductor layer. In some embodiments, the semiconductor material includes gallium nitride. In some embodiments, the light-reflection layer includes a layer of gallium.Type: GrantFiled: December 15, 2017Date of Patent: June 2, 2020Assignee: Saphlux, Inc.Inventors: Joo Won Choi, Chen Chen
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Patent number: 10665752Abstract: Aspects of the disclosure provide for mechanisms for forming air voids for semiconductor fabrication. In accordance with some embodiments, a method for forming air voids may include forming a first semiconductor layer including a first group III material and a second group III material on a substrate; forming a plurality of air voids in the first semiconductor layer by removing at least a portion of the second group III material from the first semiconductor layer; and forming a second semiconductor layer on the first semiconductor layer. The second semiconductor layer may include an epitaxial layer of a group III-V material. In some embodiments, the first group III material and the second group III material may be gallium and indium, respectively.Type: GrantFiled: December 15, 2017Date of Patent: May 26, 2020Assignee: Saphlux, Inc.Inventors: Joo Won Choi, Chen Chen, Jie Song
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Publication number: 20190189843Abstract: Aspects of the disclosure provide for mechanisms for fabricating light extraction structures for semiconductor devices (e.g., light-emitting devices). In accordance with some embodiments, a semiconductor device is provided. The semiconductor device may include: a first semiconductor layer including an epitaxial layer of a semiconductor material; a second semiconductor layer comprising an active layer; and a light-reflection layer configured to cause at least a portion of light produced by the active layer to emerge from the semiconductor device via a surface of the second semiconductor layer, wherein the light-reflection layer is positioned between the first semiconductor layer and the second semiconductor layer. In some embodiments, the semiconductor material includes gallium nitride. In some embodiments, the light-reflection layer includes a layer of gallium.Type: ApplicationFiled: December 15, 2017Publication date: June 20, 2019Inventors: Joo Won Choi, Chen Chen
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Publication number: 20190189849Abstract: Aspects of the disclosure provide for mechanisms for forming air voids for semiconductor fabrication. In accordance with some embodiments, a method for forming air voids may include forming a first semiconductor layer including a first group III material and a second group III material on a substrate; forming a plurality of air voids in the first semiconductor layer by removing at least a portion of the second group III material from the first semiconductor layer; and forming a second semiconductor layer on the first semiconductor layer. The second semiconductor layer may include an epitaxial layer of a group III-V material. In some embodiments, the first group III material and the second group III material may be gallium and indium, respectively.Type: ApplicationFiled: December 15, 2017Publication date: June 20, 2019Inventors: Joo Won Choi, Chen Chen, Jie Song
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Patent number: 9882085Abstract: The present invention relates to a method for separating epitaxial layers and growth substrates, and to a semiconductor device using same. According to the present invention, a semiconductor device is provided which comprises a supporting substrate and a plurality of semiconductor layers provided on the supporting substrate, wherein the uppermost layer of the semiconductor layers has a surface of non-uniform roughness.Type: GrantFiled: February 10, 2016Date of Patent: January 30, 2018Assignee: Seoul Viosys Co., Ltd.Inventors: Jeong Hun Heo, Joo Won Choi, Choong Min Lee, Su Jin Shin, Ki Bum Nam, Yu Dae Han, A Ram Cha Lee
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Patent number: 9537045Abstract: A method of fabricating a semiconductor device includes forming an insulation pattern including a mask region and an open region on a gallium nitride substrate, growing gallium nitride semiconductor layers to cover the insulation pattern, and patterning the semiconductor layers to form a plurality of semiconductor stacks separated from each other, the plurality of semiconductor stacks being electrically isolated from the gallium nitride substrate by the insulation pattern.Type: GrantFiled: July 10, 2015Date of Patent: January 3, 2017Assignee: Seoul Viosys Co., Ltd.Inventors: Jeong Hun Heo, Yeo Jin Yoon, Joo Won Choi, Joon Hee Lee, Chang Yeon Kim, Su Young Lee
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Publication number: 20160380149Abstract: A light emitting diode includes an N-type GaN-based semiconductor compound layer, a P-type GaN-based semiconductor compound layer, and an active region disposed between the P-type and N-type layers, the active region comprising alternately laminated well layers and barrier layers. The well layers comprise AlxInyGa1?(x+y)N, where 0?x, y?1, the barrier layers comprise AlxInyGa1?(x+y)N, where 0?x, y?1, and at least one of the barrier layers comprises first and second layers having different compositions.Type: ApplicationFiled: September 6, 2016Publication date: December 29, 2016Inventors: Joo Won CHOI, Dong Sun Lee, Gyu Beom KIM, Sang Joon LEE
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Patent number: 9514926Abstract: Embodiments of the disclosure relate to a substrate recycling method and a recycled substrate. The method includes separating a first surface of a substrate from an epitaxial layer; forming a protective layer on an opposing second surface of the substrate; electrochemically etching the first surface of the substrate; and chemically etching the electrochemically etched first surface of the substrate.Type: GrantFiled: May 4, 2015Date of Patent: December 6, 2016Assignee: SEOUL VIOSYS CO., LTD.Inventors: Su Youn Hong, Joo Won Choi, Jeong Hun Heo, Su Jin Shin, Choong Min Lee
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Patent number: 9466761Abstract: A light emitting diode (LED) having well and/or barrier layers with a superlattice structure is disclosed. An LED has an active region between an N-type GaN-based semiconductor compound layer and a P-type GaN-based semiconductor compound layer, wherein the active region comprises well and/or barrier layers with a superlattice structure. As the well and/or barrier layers with a superlattice structure are employed, it is possible to reduce occurrence of defects caused by lattice mismatch between the well layer and the barrier layer.Type: GrantFiled: March 28, 2008Date of Patent: October 11, 2016Assignee: Seoul Viosys Co., Ltd.Inventors: Joo Won Choi, Dong Seon Lee, Gyu Beom Kim, Sang Joon Lee
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Patent number: 9450141Abstract: Disclosed are a method for separating a growth substrate, a method for manufacturing a light-emitting diode, and the light-emitting diode. The method for separating a growth substrate, according to one embodiment, comprises: preparing a growth substrate; forming a sacrificial layer and a mask pattern on the growth substrate; etching the sacrificial layer by using electrochemical etching (ECE); covering the mask pattern, and forming a plurality of nitride semiconductor stacking structures which are separated from each other by an element separation area; attaching a support substrate to the plurality of semiconductor stacking structures, wherein the support substrate has a plurality of through-holes connected to the element separation area; and separating the growth substrate from the nitride semiconductor stacking structures.Type: GrantFiled: August 1, 2013Date of Patent: September 20, 2016Assignee: SEOUL VIOSYS CO., LTD.Inventors: Jeong Hun Heo, Joo Won Choi, Choong Min Lee, Young Wug Kim, Su Jin Shin, Su Youn Hong
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Patent number: 9373496Abstract: Exemplary embodiments of the present invention provide a substrate recycling method and a recycled substrate. The method includes separating a substrate having a first surface from an epitaxial layer, performing a first etching of the first surface using electrochemical etching, and performing, after the first etching, a second etching of the first surface using chemical etching, dry etching, or performing, after the first etching, chemical mechanical polishing of the first surface.Type: GrantFiled: November 21, 2013Date of Patent: June 21, 2016Assignee: Seoul Viosys Co., Ltd.Inventors: Joo Won Choi, Chang Yeon Kim, Jeong Hoon Heo, Young Wug Kim, Su Yeon Hong, Sang Wan Ryu
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Publication number: 20160172539Abstract: The present invention relates to a method for separating epitaxial layers and growth substrates, and to a semiconductor device using same. According to the present invention, a semiconductor device is provided which comprises a supporting substrate and a plurality of semiconductor layers provided on the supporting substrate, wherein the uppermost layer of the semiconductor layers has a surface of non-uniform roughness.Type: ApplicationFiled: February 10, 2016Publication date: June 16, 2016Inventors: Jeong Hun Heo, Joo Won Choi, Choong Min Lee, Su Jin Shin, Ki Bum Nam, Yu Dae Han, A Ram Cha Lee
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Patent number: 9263255Abstract: The present invention relates to a method for separating epitaxial layers and growth substrates, and to a semiconductor device using same. According to the present invention, a semiconductor device is provided which comprises a supporting substrate and a plurality of semiconductor layers provided on the supporting substrate, wherein the uppermost layer of the semiconductor layers has a surface of non-uniform roughness.Type: GrantFiled: March 19, 2013Date of Patent: February 16, 2016Assignee: SEOUL VIOSYS CO., LTD.Inventors: Jeong Hun Heo, Joo Won Choi, Choong Min Lee, Su Jin Shin, Ki Bum Nam, Yu Dae Han, A Ram Cha Lee
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Publication number: 20150380236Abstract: Embodiments of the disclosure relate to a substrate recycling method and a recycled substrate. The method includes separating a first surface of a substrate from an epitaxial layer; forming a protective layer on an opposing second surface of the substrate; electrochemically etching the first surface of the substrate; and chemically etching the electrochemically etched first surface of the substrate.Type: ApplicationFiled: May 4, 2015Publication date: December 31, 2015Inventors: Su Youn Hong, Joo Won Choi, Jeong Hun Heo, Su Jin Shin, Choong Min Lee