Patents by Inventor Rak Jun Choi

Rak Jun 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: 20150214422
    Abstract: Disclosed are a light emitting device, a method of fabricating the light emitting device, a light emitting device package, and a lighting system. The light emitting device includes a first conductive semiconductor layer, an active layer on the first conductive semiconductor layer, an electron blocking layer on the active layer, and a second conductive semiconductor layer on the electron blocking layer. The electron blocking layer includes a first electron blocking layer and an interrupted diffusion layer on the first electron blocking layer.
    Type: Application
    Filed: April 19, 2013
    Publication date: July 30, 2015
    Applicant: LG INNOTEK CO., LTD.
    Inventors: Dong Wook Kim, June O Song, Rak Jun Choi, Jeong Tak Oh
  • Publication number: 20150155436
    Abstract: A light emitting diode is disclosed. The disclosed light emitting diode includes a light emitting structure including a first-conductivity-type semiconductor layer, an active layer, and a second-conductivity-type semiconductor layer. The first-conductivity-type semiconductor layer, active layer, and second-conductivity-type semiconductor layer are disposed to be adjacent to one another in a same direction. The active layer includes well and barrier layers alternately stacked at least one time. The well layer has a narrower energy bandgap than the barrier layer. The light emitting diode also includes a mask layer disposed in the first-conductivity-type semiconductor layer, a first electrode disposed on the first-conductivity-type semiconductor layer, and a second electrode disposed on the second-conductivity-type semiconductor layer. The first-conductivity-type semiconductor layer is formed with at least one recess portion.
    Type: Application
    Filed: January 12, 2015
    Publication date: June 4, 2015
    Inventors: Myung Hoon JUNG, Hyun Chul Lim, Sul Hee Kim, Rak Jun CHOI
  • Publication number: 20150144868
    Abstract: According to one embodiment, a light-emitting element comprises: a first electrically-conductive semiconductor layer, a second electrically-conductive semiconductor layer; and an active layer which is disposed between the first electrically-conductive layer and the second electrically-conductive layer, and in which a well layer and a barrier layer are alternately laminated at least once. The active layer comprises: a first region which is disposed between a neighbouring barrier layer and well layer, and linearly reduces the energy band gap; and a second region which is disposed between a neighbouring well layer and barrier layer, and linearly increases the energy band gap. In the well layer, at least one first region and second region neighbouring the same well layer have mutually different thicknesses.
    Type: Application
    Filed: May 29, 2013
    Publication date: May 28, 2015
    Applicant: LG INNOTEK CO., LTD.
    Inventors: Young Hun Han, Seon Ho Lee, Ki Young Song, Rak Jun Choi
  • Patent number: 8952400
    Abstract: A light emitting diode is disclosed. The disclosed light emitting diode includes a light emitting structure including a first-conductivity-type semiconductor layer, an active layer, and a second-conductivity-type semiconductor layer. The first-conductivity-type semiconductor layer, active layer, and second-conductivity-type semiconductor layer are disposed to be adjacent to one another in a same direction. The active layer includes well and barrier layers alternately stacked at least one time. The well layer has a narrower energy bandgap than the barrier layer. The light emitting diode also includes a mask layer disposed in the first-conductivity-type semiconductor layer, a first electrode disposed on the first-conductivity-type semiconductor layer, and a second electrode disposed on the second-conductivity-type semiconductor layer. The first-conductivity-type semiconductor layer is formed with at least one recess portion.
    Type: Grant
    Filed: December 14, 2011
    Date of Patent: February 10, 2015
    Assignee: LG Innotek Co., Ltd.
    Inventors: Myung Hoon Jung, Hyun chul Lim, Sul Hee Kim, Rak Jun Choi
  • Publication number: 20140110663
    Abstract: A light emitting device includes a nano-structure, a first semiconductor layer on the nano-structure, an active layer on the first semiconductor layer, and a second conductive semiconductor layer on the active layer. The nano-structure includes a graphene layer provided under the first semiconductor layer to make contact with the first semiconductor layer; and a plurality of nano-textures extending from a top surface of the graphene layer to the first semiconductor layer and in contact with the first semiconductor layer.
    Type: Application
    Filed: October 17, 2013
    Publication date: April 24, 2014
    Inventors: Jae Hoon CHOI, Buem Yeon Lee, Ki Young Song, Rak Jun Choi
  • Publication number: 20140054542
    Abstract: The light emitting device includes a first conductive semiconductor layer; a second conductive semiconductor layer on the first conductive semiconductor layer; and an active layer between the first and second conductive semiconductor layers. The active layer includes a plurality of well layers and a plurality of barrier layers, wherein the well layers include a first well layer and a second well layer adjacent to the first well layer. The barrier layers include a first barrier layer disposed between the first and second well layers, and the first barrier layer includes a plurality of semiconductor layers having an energy bandgap wider than an energy bandgap of the first well layer. At least two layers of the plurality of semiconductor layers are adjacent to the first and second well layers, and have aluminum contents greater than that of the other layer.
    Type: Application
    Filed: August 19, 2013
    Publication date: February 27, 2014
    Inventors: Young Hun HAN, Rak Jun Choi, Jeong Tak Oh
  • Patent number: 8274069
    Abstract: There is provided a nitride semiconductor light emitting device. A nitride semiconductor light emitting device according to an aspect of the invention may include: an n-type nitride semiconductor layer provided on a substrate; an active layer provided on the n-type nitride semiconductor layer, and including quantum barrier layers and quantum well layers; and a p-type nitride semiconductor layer provided on the active layer, wherein each of the quantum barrier layers includes a plurality of InxGa(1-x)N layers (0<x<1) and at least one AlyGa(1-y)N layer (0?y<1), and the AlyGa(1-y)N layer is stacked between the InxGa(1-x)N layers.
    Type: Grant
    Filed: December 12, 2008
    Date of Patent: September 25, 2012
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Hun Jae Chung, Cheol Soo Sone, Sung Hwan Jang, Rak Jun Choi, Soo Min Lee
  • Publication number: 20120138994
    Abstract: A light emitting device according to an embodiment of the present invention includes a first conductive semiconductor layer providing a roughness on a upper surface thereof and including a PEC etching control layer; an active layer under the first conductive semiconductor layer; a second conductive semiconductor layer under the active layer; a reflective electrode electrically connected to the second conductive semiconductor layer; and a first electrode electrically connected to the first conductive semiconductor layer.
    Type: Application
    Filed: February 9, 2012
    Publication date: June 7, 2012
    Inventors: Dae Sung KANG, Rak Jun Choi, Sung Hoon Jung, Young Hun Han, Sung Jin Son
  • Publication number: 20120119254
    Abstract: Provided are a light emitting device, a light emitting device package, and a lighting system. The light emitting device comprises a first conductive type first semiconductor layer, an active layer, a second conductive type second semiconductor layer, a reliability enhancement layer, and a second conductive type third semiconductor layer. The active layer is disposed on the first conductive type first semiconductor layer. The second conductive type second semiconductor layer is disposed on the active layer. The reliability enhancement layer is disposed on the second conductive type second semiconductor layer. The second conductive type third semiconductor layer is disposed on the reliability enhancement layer and comprises a light extraction pattern. The reliability enhancement layer and the active layer are spaced apart from each other by a distance of 0.3 ?m to 5 ?m.
    Type: Application
    Filed: January 25, 2012
    Publication date: May 17, 2012
    Inventors: Yong Tae MOON, Yong Seon Song, Sung Hoon Jung, Joong Seo Park, Sang Jun Lee, Jeong Tak Oh, Rak Jun Choi
  • Publication number: 20120080660
    Abstract: A light emitting diode is disclosed. The disclosed light emitting diode includes a light emitting structure including a first-conductivity-type semiconductor layer, an active layer, and a second-conductivity-type semiconductor layer. The first-conductivity-type semiconductor layer, active layer, and second-conductivity-type semiconductor layer are disposed to be adjacent to one another in a same direction. The active layer includes well and barrier layers alternately stacked at least one time. The well layer has a narrower energy bandgap than the barrier layer. The light emitting diode also includes a mask layer disposed in the first-conductivity-type semiconductor layer, a first electrode disposed on the first-conductivity-type semiconductor layer, and a second electrode disposed on the second-conductivity-type semiconductor layer. The first-conductivity-type semiconductor layer is formed with at least one recess portion.
    Type: Application
    Filed: December 14, 2011
    Publication date: April 5, 2012
    Inventors: Myung Hoon JUNG, Hyun chul Lim, Sul Hee Kim, Rak Jun Choi
  • Publication number: 20110300652
    Abstract: There is provided a nitride semiconductor light emitting device and a manufacturing method of the same. The nitride semiconductor light emitting device including: a substrate for growing a nitride single crystal, the substrate having electrical conductivity; a p-type nitride semiconductor layer formed on the substrate; an active layer formed on the p-type nitride semiconductor layer, the active layer including a plurality of quantum barrier layers and a plurality of quantum well layers deposited alternately on each other; an n-type nitride semiconductor layer formed on the active layer; a p-electrode formed on a bottom of the substrate; and an n-electrode formed on a top of the n-type nitride semiconductor layer.
    Type: Application
    Filed: August 16, 2011
    Publication date: December 8, 2011
    Applicant: Samsung LED Co., Ltd.
    Inventors: Seong Eun Park, Bang Won OH, Gil Han Park, Min Ho Kim, Rak Jun Choi, Young Min Park, Hee Seok Park
  • Patent number: 7955957
    Abstract: Disclosed herein is a high-quality group III-nitride semiconductor thin film and group III-nitride semiconductor light emitting device using the same. To obtain the group III-nitride semiconductor thin film, an AlInN buffer layer is formed on a (1-102)-plane (so called r-plane) sapphire substrate by use of a MOCVD apparatus under atmospheric pressure while controlling a temperature of the substrate within a range from 850 to 950 degrees Celsius, and then, GaN-based compound, such as GaN, AlGaN or the like, is epitaxially grown on the buffer layer at a high temperature. The group III-nitride semiconductor light emitting device is fabricated by using the group III-nitride semiconductor thin film as a base layer.
    Type: Grant
    Filed: November 4, 2009
    Date of Patent: June 7, 2011
    Assignee: Samsung LED Co., Ltd.
    Inventors: Rak Jun Choi, Sakai Shiro, Naoi Yoshiki
  • Patent number: 7687814
    Abstract: Disclosed herein is a high-quality group III-nitride semiconductor thin film and group III-nitride semiconductor light emitting device using the same. To obtain the group III-nitride semiconductor thin film, an AlInN buffer layer is formed on a (1-102)-plane (so called r-plane) sapphire substrate by use of a MOCVD apparatus under atmospheric pressure while controlling a temperature of the substrate within a range from 850 to 950 degrees Celsius, and then, GaN-based compound, such as GaN, AlGaN or the like, is epitaxially grown on the buffer layer at a high temperature. The group III-nitride semiconductor light emitting device is fabricated by using the group III-nitride semiconductor thin film as a base layer.
    Type: Grant
    Filed: August 30, 2006
    Date of Patent: March 30, 2010
    Assignee: Samsung Electro-Mechanics Co., Ltd.
    Inventors: Rak Jun Choi, Sakai Shiro, Naoi Yoshiki
  • Publication number: 20100055883
    Abstract: Disclosed herein is a high-quality group III-nitride semiconductor thin film and group III-nitride semiconductor light emitting device using the same. To obtain the group III-nitride semiconductor thin film, an AlInN buffer layer is formed on a (1-102)-plane (so called r-plane) sapphire substrate by use of a MOCVD apparatus under atmospheric pressure while controlling a temperature of the substrate within a range from 850 to 950 degrees Celsius, and then, GaN-based compound, such as GaN, AlGaN or the like, is epitaxially grown on the buffer layer at a high temperature. The group III-nitride semiconductor light emitting device is fabricated by using the group III-nitride semiconductor thin film as a base layer.
    Type: Application
    Filed: November 4, 2009
    Publication date: March 4, 2010
    Applicants: SAMSUNG ELECTRO-MECHANICS CO., LTD., THE UNIVERSITY OF TOKUSHIMA
    Inventors: Rak Jun CHOI, Sakai SHIRO, Naoi YOSHIKI
  • Publication number: 20090278113
    Abstract: There is provided a nitride semiconductor light emitting device. A nitride semiconductor light emitting device according to an aspect of the invention may include: an n-type nitride semiconductor layer provided on a substrate; an active layer provided on the n-type nitride semiconductor layer, and including quantum barrier layers and quantum well layers; and a p-type nitride semiconductor layer provided on the active layer, wherein each of the quantum barrier layers includes a plurality of InxGa(1-x)N layers (0<x<1) and at least one AlyGa(1-y)N layer (0?y<1), and the AlyGa(1-y)N layer is stacked between the InxGa(1-x)N layers.
    Type: Application
    Filed: December 12, 2008
    Publication date: November 12, 2009
    Inventors: Hun Jae CHUNG, Cheol Soo SONE, Sung Hwan JANG, Rak Jun CHOI, Soo Min LEE
  • Publication number: 20090224270
    Abstract: A group III nitride semiconductor thin film and a group III nitride semiconductor light emitting device using the same. The group III nitride semiconductor thin film includes a substrate with a concave and convex portions formed thereon; a buffer layer formed on the substrate and made of a group III nitride; and an epitaxial growth layer formed on the buffer layer and made of (11-20) plane gallium nitride. The group III nitride light emitting device includes the group III nitride semiconductor thin film. The present invention allows a high quality a-plane group III nitride semiconductor thin film and a group III nitride semiconductor light emitting device using the same.
    Type: Application
    Filed: April 14, 2009
    Publication date: September 10, 2009
    Applicants: SAMSUNG ELECTRO-MECHANICS CO., LTD., THE UNIVERSITY OF TOKUSHIMA
    Inventors: Rak Jun CHOI, Naoi YOSHIKI, Sakai SHIRO
  • Publication number: 20080099781
    Abstract: A method of manufacturing a III group nitride semiconductor thin film and a method of manufacturing a nitride semiconductor light emitting device employing the III group nitride semiconductor thin film manufacturing method, the III group nitride semiconductor thin film manufacturing method including: growing a first nitride single crystal on a substrate for growing a nitride; applying an etching gas to a top surface of the first nitride single crystal to selectively form a plurality of pits in a high dislocation density area; and growing a second nitride single crystal on the first nitride single crystal to maintain the pits to be void.
    Type: Application
    Filed: September 18, 2007
    Publication date: May 1, 2008
    Inventors: Rak Jun Choi, Kureshov Vladimir, Bang Won Oh, Gil Han Park, Hee Seok Park, Seong Eun Park, Young Min Park, Min Ho Kim
  • Publication number: 20080078986
    Abstract: There is provided a nitride semiconductor light emitting device and a manufacturing method of the same. The nitride semiconductor light emitting device including: a substrate for growing a nitride single crystal, the substrate having electrical conductivity; a p-type nitride semiconductor layer formed on the substrate; an active layer formed on the p-type nitride semiconductor layer, the active layer including a plurality of quantum barrier layers and a plurality of quantum well layers deposited alternately on each other; an n-type nitride semiconductor layer formed on the active layer; a p-electrode formed on a bottom of the substrate; and an n-electrode formed on a top of the n-type nitride semiconductor layer.
    Type: Application
    Filed: September 21, 2007
    Publication date: April 3, 2008
    Inventors: Seong Eun Park, Bang Won Oh, Gil Han Park, Min Ho Kim, Rak Jun Choi, Young Min Park, Hee Seok Park
  • Patent number: 7348200
    Abstract: The invention provides a method of growing a non-polar a-plane gallium nitride. In the method, first, an r-plane substrate is prepared. Then, a low-temperature nitride-based nucleation layer is deposited on the substrate. Finally, the non-polar a-plane gallium nitride is grown on the nucleation layer. In growing the non-polar a-plane gallium nitride, a gallium source is supplied at a flow rate of about 190 to 390 ?mol/min and the flow rate of a nitrogen source is set to produce a V/III ratio of about 770 to 2310.
    Type: Grant
    Filed: March 3, 2006
    Date of Patent: March 25, 2008
    Assignees: Samsung Electro-Mechanics Co. Ltd., The University of Tokushima
    Inventors: Soo Min Lee, Rak Jun Choi, Naoi Yoshiki, Sakai Shiro, Masayoshi Koike
  • Publication number: 20070045654
    Abstract: Disclosed herein is a high-quality group III-nitride semiconductor thin film and group III-nitride semiconductor light emitting device using the same. To obtain the group III-nitride semiconductor thin film, an AlInN buffer layer is formed on a (1-102)-plane (so called r-plane) sapphire substrate by use of a MOCVD apparatus under atmospheric pressure while controlling a temperature of the substrate within a range from 850 to 950 degrees Celsius, and then, GaN-based compound, such as GaN, AlGaN or the like, is epitaxially grown on the buffer layer at a high temperature. The group III-nitride semiconductor light emitting device is fabricated by using the group III-nitride semiconductor thin film as a base layer.
    Type: Application
    Filed: August 30, 2006
    Publication date: March 1, 2007
    Inventors: Rak Jun Choi, Sakai Shiro, Naoi Yoshiki