Patents by Inventor A Ram Cha LEE

A Ram Cha LEE 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: 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
  • Patent number: 9882085
    Abstract: 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: Grant
    Filed: February 10, 2016
    Date of Patent: January 30, 2018
    Assignee: 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
  • Patent number: 9859108
    Abstract: Disclosed are a substrate regeneration method and a regenerated substrate. The substrate regeneration method comprises preparing a substrate having a surface separated from an epitaxial layer. The separated surface includes a convex portion and a concave portion, and the convex portion is comparatively flatter than the concave portion. A crystalline restoration layer is grown on the separated surface. The crystalline restoration layer is grown on the convex portion. Furthermore, a surface roughness improvement layer is grown on the crystalline restoration layer, thereby providing a continuous surface. Accordingly, it is possible to provide a regenerated substrate, which has a flat surface, without using physical polishing or chemical etching technology.
    Type: Grant
    Filed: December 3, 2015
    Date of Patent: January 2, 2018
    Assignee: Seoul Viosys Co., Ltd.
    Inventors: Chang Suk Han, Hwa Mok Kim, Mi So Ko, A Ram Cha Lee, Daewoong Suh
  • Patent number: 9520533
    Abstract: A UV light emitting device and a method for fabricating the same are disclosed. The method includes forming a first super-lattice layer including AlxGa(1-x)N on a substrate, forming a sacrificial layer including AlzGa(1-z)N on the first super-lattice layer, partially removing the sacrificial layer, forming an epitaxial layer on the sacrificial layer, and separating the substrate from the epitaxial layer, wherein the sacrificial layer includes voids, the substrate is separated from the epitaxial layer at the sacrificial layer, and forming an epitaxial layer includes forming an n-type semiconductor layer including n-type AluGa(1-u)N (0<u?z?x<1). With this structure, the light emitting device can emit UV light and be separated from the substrate.
    Type: Grant
    Filed: October 5, 2015
    Date of Patent: December 13, 2016
    Assignee: SEOUL VIOSYS CO., LTD.
    Inventors: Chang Suk Han, Hwa Mok Kim, Mi So Ko, A Ram Cha Lee, Dae Woong Suh
  • 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
  • Publication number: 20160172539
    Abstract: 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: Application
    Filed: February 10, 2016
    Publication date: June 16, 2016
    Inventors: Jeong Hun Heo, Joo Won Choi, Choong Min Lee, Su Jin Shin, Ki Bum Nam, Yu Dae Han, A Ram Cha Lee
  • Publication number: 20160155628
    Abstract: Disclosed are a substrate regeneration method and a regenerated substrate. The substrate regeneration method comprises preparing a substrate having a surface separated from an epitaxial layer. The separated surface includes a convex portion and a concave portion, and the convex portion is comparatively flatter than the concave portion. A crystalline restoration layer is grown on the separated surface. The crystalline restoration layer is grown on the convex portion. Furthermore, a surface roughness improvement layer is grown on the crystalline restoration layer, thereby providing a continuous surface. Accordingly, it is possible to provide a regenerated substrate, which has a flat surface, without using physical polishing or chemical etching technology.
    Type: Application
    Filed: December 3, 2015
    Publication date: June 2, 2016
    Inventors: Chang Suk Han, Hwa Mok Kim, Mi So Ko, A Ram Cha Lee, Daewoong Suh
  • 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
  • Patent number: 9263255
    Abstract: 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: Grant
    Filed: March 19, 2013
    Date of Patent: February 16, 2016
    Assignee: 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
  • Publication number: 20160035935
    Abstract: A UV light emitting device and a method for fabricating the same are disclosed. The method includes forming a first super-lattice layer including AlxGa(1-x)N on a substrate, forming a sacrificial layer including AlzGa(1-z)N on the first super-lattice layer, partially removing the sacrificial layer, forming an epitaxial layer on the sacrificial layer, and separating the substrate from the epitaxial layer, wherein the sacrificial layer includes voids, the substrate is separated from the epitaxial layer at the sacrificial layer, and forming an epitaxial layer includes forming an n-type semiconductor layer including n-type AluGa(1-u)N (0<u?z?x<1). With this structure, the light emitting device can emit UV light and be separated from the substrate.
    Type: Application
    Filed: October 5, 2015
    Publication date: February 4, 2016
    Inventors: Chang Suk Han, Hwa Mok Kim, Mi So Ko, A Ram Cha Lee, Dae Woong Suh
  • 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: 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
  • Publication number: 20150069418
    Abstract: 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: Application
    Filed: March 19, 2013
    Publication date: March 12, 2015
    Inventors: Jeong Hun Heo, Joo Won Choi, Choong Min Lee, Su Jin Shin, Ki Bum Nam, Yu Dae Han, A Ram Cha Lee
  • Publication number: 20150041760
    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: October 28, 2014
    Publication date: February 12, 2015
    Inventors: Chang Suk HAN, Hwa Mok Kim, Hyo Shik Choi, Mi So Ko, A Ram Cha Lee
  • Publication number: 20130256630
    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: Application
    Filed: March 29, 2013
    Publication date: October 3, 2013
    Applicant: Seoul Opto Device Co., Ltd.
    Inventors: Chang Suk HAN, Hwa Mok KIM, Hyo Shik CHOI, Mi So KO, A Ram Cha LEE