Patents by Inventor Hyo Shik CHOI

Hyo Shik 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).

  • Publication number: 20230299229
    Abstract: A display apparatus includes multiple pixels. The pixels can emit one or more colors of light. Light of the same color emitted by two or more of the pixels can have wavelengths that differ by no more than one percent. The pixels can include a stacked structure including two or more subpixels, with each subpixel emitting light of a different color than the other subpixels in the stacked structure.
    Type: Application
    Filed: May 22, 2023
    Publication date: September 21, 2023
    Applicant: SEOUL VIOSYS CO., LTD.
    Inventors: Ji Hoon PARK, Ji Hun KANG, Chae Hon KIM, Yong Hyun BAEK, Hyo Shik CHOI
  • Patent number: 11658263
    Abstract: A method of fabricating a light emitting device includes (i) determining whether each measurement location is defective or not based on a measurement result of the emission wavelength of each location, (ii) forming a test stacked structure by combining one of the first wafers, one of the second wafers, and one of the third wafers in a set of wafers, and (iii) calculating a combination yield of the test stacked structure based on a count of defective measurement locations that overlap in the test stacked structure.
    Type: Grant
    Filed: March 5, 2021
    Date of Patent: May 23, 2023
    Assignee: Seoul Viosys Co., Ltd.
    Inventors: Ji Hoon Park, Ji Hun Kang, Chae Hon Kim, Yong Hyun Baek, Hyo Shik Choi
  • Publication number: 20210280738
    Abstract: A method of fabricating a light emitting device includes (i) determining whether each measurement location is defective or not based on a measurement result of the emission wavelength of each location, (ii) forming a test stacked structure by combining one of the first wafers, one of the second wafers, and one of the third wafers in a set of wafers, and (iii) calculating a combination yield of the test stacked structure based on a count of defective measurement locations that overlap in the test stacked structure.
    Type: Application
    Filed: March 5, 2021
    Publication date: September 9, 2021
    Applicant: SEOUL VIOSYS CO., LTD.
    Inventors: Ji Hoon PARK, Ji Hun KANG, Chae Hon KIM, Yong Hyun BAEK, Hyo Shik CHOI
  • Patent number: 11049995
    Abstract: A long-wavelength light emitting device is disclosed. The long-wavelength light emitting device comprises: a first conductive semi-conductor layer; an active layer that is located on the first conductive semi-conductor layer and that has a quantum well structure; and a second conductive semi-conductor layer that is located on the active layer. The active layer comprises: one or more well layers including a nitride-based semi-conductor having 21% or more In; two barrier layers located in upper and lower parts of the well layers, and located between the well layers and the barrier layers, wherein the upper capping layers have a bigger band-gap energy relative to the barrier layers, and the upper capping layers and the well layers are in contact.
    Type: Grant
    Filed: May 23, 2017
    Date of Patent: June 29, 2021
    Assignee: SEOUL VIOSYS CO., LTD.
    Inventors: Hong Jae Yoo, Hyo Shik Choi, Hyung Ju Lee
  • Publication number: 20190296187
    Abstract: A long-wavelength light emitting device is disclosed. The long-wavelength light emitting device comprises: a first conductive semi-conductor layer; an active layer that is located on the first conductive semi-conductor layer and that has a quantum well structure; and a second conductive semi-conductor layer that is located on the active layer. The active layer comprises: one or more well layers including a nitride-based semi-conductor having 21% or more In; two barrier layers located in upper and lower parts of the well layers, and located between the well layers and the barrier layers, wherein the upper capping layers have a bigger band-gap energy relative to the barrier layers, and the upper capping layers and the well layers are in contact.
    Type: Application
    Filed: May 23, 2017
    Publication date: September 26, 2019
    Inventors: Hong Jae YOO, Hyo Shik CHOI, Hyung Ju LEE
  • Patent number: 10374123
    Abstract: Disclosed herein is a UV light emitting device. The UV light emitting device includes a first conductive type semi-conductor layer, an anti-cracking layer disposed on the first conductive type semiconductor layer, an active layer disposed on the anti-cracking layer, and a second conductive type semiconductor layer disposed on the active layer, wherein the anti-cracking layer includes first lattice points and second lattice points disposed at an interface between the first conductive type semiconductor layer and the anti-cracking layer, the first lattice points are connected to lattices of the first conductive type semiconductor layer, and the second lattice points are not connected to the lattices of the first conductive type semiconductor layer.
    Type: Grant
    Filed: March 28, 2016
    Date of Patent: August 6, 2019
    Assignee: SEOUL VIOSYS CO., LTD.
    Inventors: Chang Seok Han, Woo Chul Kwak, Hyo Shik Choi, Jung Hwan Hwang, Chang Geun Jang
  • Patent number: 10177273
    Abstract: A UV light emitting device includes: an n-type contact layer including an AlGaN layer or an AlInGaN layer; a p-type contact layer including a AlGaN layer or an AlInGaN layer; and an active layer of a multi-quantum well structure placed between the n-type contact layer and the p-type contact layer. The active area of the multi-quantum well structure includes barrier layers and well layers. The well layers include electrons and holes present according to probability distributions thereof. The barrier layers are formed of AlInGaN or AlGaN and have an Al content of 10% to 30%. At least one of the barrier layers disposed between the well layers has a smaller thickness than of the well layers and at least one of the barrier layers placed between the well layers has a thickness and a band gap preventing electrons and holes injected into and confined in a well layer adjacent to the barrier layer from spreading into another adjacent well layer.
    Type: Grant
    Filed: July 28, 2015
    Date of Patent: January 8, 2019
    Assignee: Seoul Viosys Co., Ltd.
    Inventors: Chang Suk Han, Hwa Mok Kim, Hyo Shik Choi, Mi So Ko, A Ram Cha Lee
  • Patent number: 10164150
    Abstract: Disclosed is a near UV light emitting device. The light emitting device includes an n-type contact layer, a p-type contact layer, an active area of a multi-quantum well structure disposed between the n-type contact layer and the p-type contact layer, and at least one electron control layer disposed between the n-type contact layer and the active area. Each of the n-type contact layer and the p-type contact layer includes an AlInGaN or AlGaN layer, and the electron control layer is formed of AlInGaN or AlGaN. In addition, the electron control layer contains a larger amount of Al than adjacent layers to obstruct flow of electrons moving into the active area. Accordingly, electron mobility is deteriorated, thereby improving recombination rate of electrons and holes in the active area.
    Type: Grant
    Filed: April 11, 2016
    Date of Patent: December 25, 2018
    Assignee: Seoul Viosys Co., Ltd.
    Inventors: Chang Suk Han, Hwa Mok Kim, Hyo Shik Choi, Mi So Ko, A Ram Cha Lee
  • Publication number: 20180090640
    Abstract: Disclosed herein is a UV light emitting device. The UV light emitting device includes a first conductive type semi-conductor layer, an anti-cracking layer disposed on the first conductive type semiconductor layer, an active layer disposed on the anti-cracking layer, and a second conductive type semiconductor layer disposed on the active layer, wherein the anti-cracking layer includes first lattice points and second lattice points disposed at an interface between the first conductive type semiconductor layer and the anti-cracking layer, the first lattice points are connected to lattices of the first conductive type semiconductor layer, and the second lattice points are not connected to the lattices of the first conductive type semiconductor layer.
    Type: Application
    Filed: March 28, 2016
    Publication date: March 29, 2018
    Inventors: Chang Seok Han, Woo Chul Kwak, Hyo Shik Choi, Jung Hwan Hwang, Chang Geun Jang
  • Patent number: 9911898
    Abstract: Disclosed is an ultraviolet light-emitting device. The light-emitting device includes: an n-type contact layer including a GaN layer; a p-type contact layer including an AlGaN or AlInGaN layer; and an active region of multiple quantum well structure positioned between the n-type contact layer and the p-type contact layer. In addition, the active region of multiple quantum well structure includes a GaN or InGaN layer with a thickness less than 2 nm, radiating an ultraviolet ray with a peak wavelength of 340 nm to 360 nm.
    Type: Grant
    Filed: January 12, 2017
    Date of Patent: March 6, 2018
    Assignee: Seoul Viosys Co., Ltd.
    Inventors: Hyo Shik Choi, Jung Hwan Hwang, Chang Suk Han
  • Publication number: 20170125634
    Abstract: Disclosed is an ultraviolet light-emitting device. The light-emitting device includes: an n-type contact layer including a GaN layer; a p-type contact layer including an AlGaN or AlInGaN layer; and an active region of multiple quantum well structure positioned between the n-type contact layer and the p-type contact layer. In addition, the active region of multiple quantum well structure includes a GaN or InGaN layer with a thickness less than 2 nm, radiating an ultraviolet ray with a peak wavelength of 340 nm to 360 nm.
    Type: Application
    Filed: January 12, 2017
    Publication date: May 4, 2017
    Inventors: Hyo Shik Choi, Jung Hwan Hwang, Chang Suk Han
  • Patent number: 9577144
    Abstract: Disclosed is an ultraviolet light-emitting device. The light-emitting device includes: an n-type contact layer including a GaN layer; a p-type contact layer including an AlGaN or AlInGaN layer; and an active region of multiple quantum well structure positioned between the n-type contact layer and the p-type contact layer. In addition, the active region of multiple quantum well structure includes a GaN or InGaN layer with a thickness less than 2 nm, radiating an ultraviolet ray with a peak wavelength of 340 nm to 360 nm.
    Type: Grant
    Filed: March 7, 2014
    Date of Patent: February 21, 2017
    Assignee: Seoul Viosys Co., Ltd.
    Inventors: Hyo Shik Choi, Jung Hwan Hwang, Chang Suk Han
  • Patent number: 9543476
    Abstract: A UV light emitting diode and a method of fabricating the same are provided. The light emitting diode includes an active area between an n-type nitride-based semiconductor layer and a p-type nitride-based semiconductor layer, wherein the active area includes a plurality of barrier layers containing Al, a plurality of well layers containing Al and alternately arranged with the barrier layer, and at least one conditioning layer. Each conditioning layer is placed between the well layer and the barrier layer adjacent to the well layer and is formed of a binary nitride semiconductor. The design of the conditioning layer can reduce stress of the active area while allowing uniform control of the composition of the well layers and/or the barrier layers.
    Type: Grant
    Filed: November 28, 2014
    Date of Patent: January 10, 2017
    Assignee: SEOUL VIOSYS CO., LTD.
    Inventors: Ki Yon Park, Jeong Hun Heo, Hwa Mok Kim, Chang Suk Han, Hyo Shik Choi
  • Publication number: 20160225950
    Abstract: Disclosed is a near UV light emitting device. The light emitting device includes an n-type contact layer, a p-type contact layer, an active area of a multi-quantum well structure disposed between the n-type contact layer and the p-type contact layer, and at least one electron control layer disposed between the n-type contact layer and the active area. Each of the n-type contact layer and the p-type contact layer includes an AlInGaN or AlGaN layer, and the electron control layer is formed of AlInGaN or AlGaN. In addition, the electron control layer contains a larger amount of Al than adjacent layers to obstruct flow of electrons moving into the active area. Accordingly, electron mobility is deteriorated, thereby improving recombination rate of electrons and holes in the active area.
    Type: Application
    Filed: April 11, 2016
    Publication date: August 4, 2016
    Inventors: Chang Suk HAN, Hwa Mok KIM, Hyo Shik CHOI, Mi So KO, A Ram Cha LEE
  • Patent number: 9312447
    Abstract: Disclosed is a near UV light emitting device. The light emitting device includes an n-type contact layer, a p-type contact layer, an active area of a multi-quantum well structure disposed between the n-type contact layer and the p-type contact layer, and at least one electron control layer disposed between the n-type contact layer and the active area. Each of the n-type contact layer and the p-type contact layer includes an AlInGaN or AlGaN layer, and the electron control layer is formed of AlInGaN or AlGaN. In addition, the electron control layer contains a larger amount of Al than adjacent layers to obstruct flow of electrons moving into the active area. Accordingly, electron mobility is deteriorated, thereby improving recombination rate of electrons and holes in the active area.
    Type: Grant
    Filed: October 28, 2014
    Date of Patent: April 12, 2016
    Assignee: Seoul Viosys Co., Ltd.
    Inventors: Chang Suk Han, Hwa Mok Kim, Hyo Shik Choi, Mi So Ko, A Ram Cha Lee
  • Publication number: 20160064598
    Abstract: Disclosed is an ultraviolet light-emitting device. The light-emitting device includes: an n-type contact layer including a GaN layer; a p-type contact layer including an AlGaN or AlInGaN layer; and an active region of multiple quantum well structure positioned between the n-type contact layer and the p-type contact layer. In addition, the active region of multiple quantum well structure includes a GaN or InGaN layer with a thickness less than 2 nm, radiating an ultraviolet ray with a peak wavelength of 340 nm to 360 nm.
    Type: Application
    Filed: March 7, 2014
    Publication date: March 3, 2016
    Inventors: Hyo Shik Choi, Jung Hwan Hwang, Chang Suk Han
  • Patent number: 9252012
    Abstract: A method of fabricating a nitride substrate including preparing a growth substrate and disposing a sacrificial layer on the growth substrate. The sacrificial layer includes a nitride horizontal etching layer including an indium-based nitride and an upper nitride sacrificial layer formed on the nitride horizontal etching layer. The method of fabricating the nitride substrate also includes horizontally etching the nitride horizontal etching layer, forming at least one etching hole at least partially through the upper nitride sacrificial layer such that the at least one etching hole expands in the nitride horizontal etching layer in a horizontal direction during horizontal etching of the nitride horizontal etching layer, forming a nitride epitaxial layer on the upper nitride sacrificial layer by hydride vapor phase epitaxy (HVPE) and separating the nitride epitaxial layer from the growth substrate at the nitride horizontal etching layer.
    Type: Grant
    Filed: August 24, 2015
    Date of Patent: February 2, 2016
    Assignee: Seoul Viosys Co., Ltd.
    Inventors: Ki Yon Park, Hwa Mok Kim, Chang Suk Han, Hyo Shik Choi, Mi So Ko
  • Patent number: 9224913
    Abstract: Disclosed herein is an ultraviolet (UV) light emitting device. The light emitting device includes an n-type contact layer including a GaN layer; a p-type contact layer including a GaN layer; and an active layer of a multi-quantum well structure disposed between the n-type contact layer and the p-type contact layer, the active area configured to emit near ultraviolet light at wavelengths of 365 nm to 309 nm.
    Type: Grant
    Filed: March 29, 2013
    Date of Patent: December 29, 2015
    Assignee: Seoul Viosys Co., Ltd.
    Inventors: Chang Suk Han, Hwa Mok Kim, Hyo Shik Choi, Mi So Ko, A Ram Cha Lee
  • Publication number: 20150364319
    Abstract: A method of fabricating a nitride substrate including preparing a growth substrate and disposing a sacrificial layer on the growth substrate. The sacrificial layer includes a nitride horizontal etching layer including an indium-based nitride and an upper nitride sacrificial layer formed on the nitride horizontal etching layer. The method of fabricating the nitride substrate also includes horizontally etching the nitride horizontal etching layer, forming at least one etching hole at least partially through the upper nitride sacrificial layer such that the at least one etching hole expands in the nitride horizontal etching layer in a horizontal direction during horizontal etching of the nitride horizontal etching layer, forming a nitride epitaxial layer on the upper nitride sacrificial layer by hydride vapor phase epitaxy (HVPE) and separating the nitride epitaxial layer from the growth substrate at the nitride horizontal etching layer.
    Type: Application
    Filed: August 24, 2015
    Publication date: December 17, 2015
    Inventors: Ki Yon PARK, Hwa Mok KIM, Chang Suk HAN, Hyo Shik CHOI, Mi So KO
  • Publication number: 20150333218
    Abstract: A UV light emitting device includes: an n-type contact layer including an AlGaN layer or an AlInGaN layer; a p-type contact layer including a AlGaN layer or an AlInGaN layer; and an active layer of a multi-quantum well structure placed between the n-type contact layer and the p-type contact layer. The active area of the multi-quantum well structure includes barrier layers and well layers. The well layers include electrons and holes present according to probability distributions thereof. The barrier layers are formed of AlInGaN or AlGaN and have an Al content of 10% to 30%. At least one of the barrier layers disposed between the well layers has a smaller thickness than of the well layers and at least one of the barrier layers placed between the well layers has a thickness and a band gap preventing electrons and holes injected into and confined in a well layer adjacent to the barrier layer from spreading into another adjacent well layer.
    Type: Application
    Filed: July 28, 2015
    Publication date: November 19, 2015
    Inventors: Chang Suk HAN, Hwa Mok Kim, Hyo Shik Choi, Mi So Ko, A Ram Cha Lee