Patents by Inventor Yoshiki Naoi

Yoshiki Naoi 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: 8039280
    Abstract: The present invention provides a method of fabricating a light emitting diode, which comprises the steps of forming a compound semiconductor layer on a substrate, the compound semiconductor layer including a lower semiconductor layer, an active layer and an upper semiconductor layer; and scratching a surface of the substrate by rubbing the substrate with an abrasive. According to the present invention, the abrasive is used to rub and scratch the surface of the light emitting diode, thereby making it possible to cause the light emitted from the active layer to effectively exit to the outside. Therefore, the light extraction efficiency of the light emitting diode can be improved.
    Type: Grant
    Filed: May 16, 2008
    Date of Patent: October 18, 2011
    Assignees: Seoul Opto Device Co., Ltd., The University of Tokushima
    Inventors: Shiro Sakai, Yoshiki Naoi
  • Publication number: 20100171136
    Abstract: The present invention provides a method of fabricating a light emitting diode, which comprises the steps of forming a compound semiconductor layer on a substrate, the compound semiconductor layer including a lower semiconductor layer, an active layer and an upper semiconductor layer; and scratching a surface of the substrate by rubbing the substrate with an abrasive. According to the present invention, the abrasive is used to rub and scratch the surface of the light emitting diode, thereby making it possible to cause the light emitted from the active layer to effectively exit to the outside. Therefore, the light extraction efficiency of the light emitting diode can be improved.
    Type: Application
    Filed: May 16, 2008
    Publication date: July 8, 2010
    Inventors: Shiro Sakai, Yoshiki Naoi
  • Patent number: 7005685
    Abstract: A GaN-based compound semiconductor device formed by sequentially forming, on a substrate, a GaN-based buffer layer and a GaN-based compound semiconductor layer. AlxGa1-xN1-yPy or AlxGa1-xN1-yAsy (0?x?1, 0<y<1) is used as the GaN-based buffer layer. N in AlxGa1-xN is partially substituted by P or As, whereby a buffer layer is grown at a high temperature. Thus, a difference in processing temperature between the process for growing a buffer layer and processes before and after the process is reduced. The GaN-based compound semiconductor layer formed on the buffer layer comprises a GaN-based layer, an n-type clad layer, a light-emitting layer, and a p-type clad layer. A multiple quantum well (MQW) layer formed from GaNP or GaNAs and GaN is inserted between the GaN-based layers, thereby reducing a dislocation density of the GaN-based layers.
    Type: Grant
    Filed: February 28, 2003
    Date of Patent: February 28, 2006
    Assignees: Nitride Semiconductors Co., Ltd.
    Inventors: Shiro Sakai, Yoshiki Naoi, Masashi Tsukihara
  • Publication number: 20030222266
    Abstract: A GaN-based compound semiconductor device formed by sequentially forming, on a substrate, a GaN-based buffer layer and a GaN-based compound semiconductor layer. AlxGa1-xN1-yPy or AlxGa1-xN1-yAsy (0≦x≦1, 0<y<1) is used as the GaN-based buffer layer. N in AlxGa1-xN is partially substituted by P or As, whereby a buffer layer is grown at a high temperature. Thus, a difference in processing temperature between the process for growing a buffer layer and processes before and after the process is reduced. The GaN-based compound semiconductor layer formed on the buffer layer comprises a GaN-based layer, an n-type clad layer, a light-emitting layer, and a p-type clad layer. A multiple quantum well (MQW) layer formed from GaNP or GaNAs and GaN is inserted between the GaN-based layers, thereby reducing a dislocation density of the GaN-based layers.
    Type: Application
    Filed: February 28, 2003
    Publication date: December 4, 2003
    Inventors: Shiro Sakai, Yoshiki Naoi, Masashi Tsukihara