Patents by Inventor Shiro Sakai

Shiro Sakai 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: 8129729
    Abstract: A light-emitting device operating on a high drive voltage and a small drive current. LEDs (1) are two-dimensionally formed on an insulating substrate (10) of e.g., sapphire monolithically and connected in series to form an LED array. Two such LED arrays are connected to electrodes (32) in inverse parallel. Air-bridge wiring (28) is formed between the LEDs (1) and between the LEDs (1) and electrodes (32). The LED arrays are arranged zigzag to form a plurality of LEDs (1) to produce a high drive voltage and a small drive current. Two LED arrays are connected in inverse parallel, and therefore an AC power supply can be used as the power supply.
    Type: Grant
    Filed: April 1, 2008
    Date of Patent: March 6, 2012
    Assignee: Seoul Semiconductor Co., Ltd.
    Inventors: Shiro Sakai, Jin-Ping Ao, Yasuo Ono
  • Publication number: 20120021546
    Abstract: The present invention provides a method of fabricating a semiconductor substrate and a method of fabricating a light emitting device. The method includes forming a first semiconductor layer on a substrate, forming a metallic material layer on the first semiconductor layer, forming a second semiconductor layer on the first semiconductor layer and the metallic material layer, wherein a void is formed in a first portion of the first semiconductor layer under the metallic material layer during formation of the second semiconductor layer, and separating the substrate from the second semiconductor layer by etching at least a second portion of the first semiconductor layer using a chemical solution.
    Type: Application
    Filed: July 21, 2011
    Publication date: January 26, 2012
    Applicant: SEOUL OPTO DEVICE CO., LTD.
    Inventors: Chang Youn Kim, Shiro Sakai, Hwa Mok Kim, Joon Hee Lee, Soo Young Moon, Kyoung Wan Kim
  • Patent number: 8097889
    Abstract: A light-emitting device operating on a high drive voltage and a small drive current. LEDs (1) are two-dimensionally formed on an insulating substrate (10) of e.g., sapphire monolithically and connected in series to form an LED array. Two such LED arrays are connected to electrodes (32) in inverse parallel. Air-bridge wiring (28) is formed between the LEDs (1) and between the LEDs (1) and electrodes (32). The LED arrays are arranged zigzag to form a plurality of LEDs (1) to produce a high drive voltage and a small drive current. Two LED arrays are connected in inverse parallel, and therefore an AC power supply can be used as the power supply.
    Type: Grant
    Filed: January 12, 2009
    Date of Patent: January 17, 2012
    Assignee: Seoul Semiconductor Co., Ltd.
    Inventors: Shiro Sakai, Jin-Ping Ao, Yasuo Ono
  • Patent number: 8084774
    Abstract: A light-emitting device operating on a high drive voltage and a small drive current. LEDs (1) are two-dimensionally formed on an insulating substrate (10) of e.g., sapphire monolithically and connected in series to form an LED array. Two such LED arrays are connected to electrodes (32) in inverse parallel. Air-bridge wiring (28) is formed between the LEDs (1) and between the LEDs (1) and electrodes (32). The LED arrays are arranged zigzag to form a plurality of LEDs (1) to produce a high drive voltage and a small drive current. Two LED arrays are connected in inverse parallel, and therefore an AC power supply can be used as the power supply.
    Type: Grant
    Filed: January 12, 2009
    Date of Patent: December 27, 2011
    Assignee: Seoul Semiconductor Co., Ltd.
    Inventors: Shiro Sakai, Jin-Ping Ao, Yasuo Ono
  • Publication number: 20110309461
    Abstract: A photodetector and a spectrum detector, which can be miniaturized and do not require a complicated alignment of an optical axis, are disclosed. A photodetector comprises a substrate and a semiconductor that is formed on the substrate and has a plurality of convex portions. The photodetector detects light transmitted through the plurality of convex portions among light incident on the plurality of convex portions. Accordingly, it is possible to detect light with a specific peak wavelength without using an optical component such as a diffraction grating or prism, so that a small-sized photodetector that does not require a complicated alignment of the optical axis in an optical system may be implemented.
    Type: Application
    Filed: March 30, 2009
    Publication date: December 22, 2011
    Applicant: SEOUL OPTO DEVICE CO., LTD.
    Inventor: Shiro Sakai
  • 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
  • Patent number: 8026119
    Abstract: The present invention provides a method of fabricating a semiconductor substrate and a method of fabricating a light emitting device. The method includes forming a first semiconductor layer on a substrate, forming a metallic material layer on the first semiconductor layer, forming a second semiconductor layer on the first semiconductor layer and the metallic material layer, wherein a void is formed in a first portion of the first semiconductor layer under the metallic material layer during formation of the second semiconductor layer, and separating the substrate from the second semiconductor layer by etching at least a second portion of the first semiconductor layer using a chemical solution.
    Type: Grant
    Filed: August 26, 2010
    Date of Patent: September 27, 2011
    Assignee: Seoul Opto Device Co., Ltd.
    Inventors: Chang Youn Kim, Shiro Sakai, Hwa Mok Kim, Joon Hee Lee, Soo Young Moon, Kyoung Wan Kim
  • Publication number: 20110193236
    Abstract: The present invention provides a method of manufacturing a gallium nitride (GaN) substrate on a heterogeneous substrate at low cost while realizing performance improvement and long operational lifespan of semiconductor devices, such as LEDs or laser diodes, which are manufactured using the GaN substrate. The semiconductor substrate includes a substrate, a first semiconductor layer arranged on the substrate, a mask arranged on a first region of the first semiconductor layer, a metallic material layer arranged on the first semiconductor layer and the mask, the metallic material layer being arranged in a direction intersecting the mask, a second semiconductor layer arranged on the first semiconductor layer and the metallic material layer, and a cavity in the first semiconductor layer and arranged under the metallic material layer.
    Type: Application
    Filed: September 3, 2010
    Publication date: August 11, 2011
    Applicant: SEOUL OPTO DEVICE CO., LTD.
    Inventor: Shiro SAKAI
  • Publication number: 20110151647
    Abstract: Exemplary embodiments of the present invention provide a method of fabricating a semiconductor substrate, the method including forming a first semiconductor layer on a substrate, forming a metallic material layer on the first semiconductor layer, forming a second semiconductor layer on the first semiconductor layer and the metallic material layer, etching the substrate using a solution to remove the metallic material layer and a portion of the first semiconductor layer, and forming a cavity in the first semiconductor layer under where the metallic material layer was removed.
    Type: Application
    Filed: February 10, 2011
    Publication date: June 23, 2011
    Applicant: SEOUL OPTO DEVICE CO., LTD.
    Inventor: Shiro Sakai
  • Patent number: 7956367
    Abstract: A light-emitting device operating on a high drive voltage and a small drive current. LEDs (1) are two-dimensionally formed on an insulating substrate (10) of e.g., sapphire monolithically and connected in series to form an LED array. Two such LED arrays are connected to electrodes (32) in inverse parallel. Air-bridge wiring (28) is formed between the LEDs (1) and between the LEDs (1) and electrodes (32). The LED arrays are arranged zigzag to form a plurality of LEDs (1) to produce a high drive voltage and a small drive current. Two LED arrays are connected in inverse parallel, and therefore an AC power supply can be used as the power supply.
    Type: Grant
    Filed: February 12, 2007
    Date of Patent: June 7, 2011
    Assignee: Seoul Semiconductor Co., Ltd.
    Inventors: Shiro Sakai, Jin-Ping Ao, Yasuo Ono
  • Publication number: 20110073879
    Abstract: A light-emitting device operating on a high drive voltage and a small drive current. LEDs (1) are two-dimensionally formed on an insulating substrate (10) of e.g., sapphire monolithically and connected in series to form an LED array. Two such LED arrays are connected to electrodes (32) in inverse parallel. Air-bridge wiring (28) is formed between the LEDs (1) and between the LEDs (1) and electrodes (32). The LED arrays are arranged zigzag to form a plurality of LEDs (1) to produce a high drive voltage and a small drive current. Two LED arrays are connected in inverse parallel, and therefore an AC power supply can be used as the power supply.
    Type: Application
    Filed: December 2, 2010
    Publication date: March 31, 2011
    Applicant: SEOUL SEMICONDUCTOR CO., LTD.
    Inventors: Shiro SAKAI, Jin-Ping AO, Yasuo ONO
  • Publication number: 20110053303
    Abstract: The present invention provides a method of fabricating a semiconductor substrate and a method of fabricating a light emitting device. The method includes forming a first semiconductor layer on a substrate, forming a metallic material layer on the first semiconductor layer, forming a second semiconductor layer on the first semiconductor layer and the metallic material layer, wherein a void is formed in a first portion of the first semiconductor layer under the metallic material layer during formation of the second semiconductor layer, and separating the substrate from the second semiconductor layer by etching at least a second portion of the first semiconductor layer using a chemical solution.
    Type: Application
    Filed: August 26, 2010
    Publication date: March 3, 2011
    Applicant: SEOUL OPTO DEVICE CO., LTD.
    Inventors: Chang Youn Kim, Shiro Sakai, Hwa Mok Kim, Joon Hee Lee, Soo Young Moon, Kyoung Wan Kim
  • Patent number: 7897982
    Abstract: A light-emitting device operating on a high drive voltage and a small drive current. LEDs (1) are two-dimensionally formed on an insulating substrate (10) of e.g., sapphire monolithically and connected in series to form an LED array. Two such LED arrays are connected to electrodes (32) in inverse parallel. Air-bridge wiring (28) is formed between the LEDs (1) and between the LEDs (1) and electrodes (32). The LED arrays are arranged zigzag to form a plurality of LEDs (1) to produce a high drive voltage and a small drive current. Two LED arrays are connected in inverse parallel, and therefore an AC power supply can be used as the power supply.
    Type: Grant
    Filed: June 16, 2008
    Date of Patent: March 1, 2011
    Assignee: Seoul Semiconductor Co., Ltd.
    Inventors: Shiro Sakai, Jin-Ping Ao, Yasuo Ono
  • Publication number: 20100314661
    Abstract: The present invention provides a fabrication method of a semiconductor substrate, by which a planar GaN substrate that is easily separated can be fabricated on a heterogeneous substrate, and a semiconductor device which is fabricated using the GaN substrate. The semiconductor substrate comprises a substrate, a first semiconductor layer arranged on the substrate, a metallic material layer arranged on the first semiconductor layer, a second semiconductor layer arranged on the first semiconductor layer and the metallic material layer, and voids formed in the first semiconductor layer under the metallic material layer.
    Type: Application
    Filed: December 30, 2009
    Publication date: December 16, 2010
    Applicant: Seoul Opto Device Co., Ltd.
    Inventor: Shiro SAKAI
  • Publication number: 20100208762
    Abstract: A laser diode having nano patterns is disposed on a substrate. A first conductive-type clad layer is disposed on the substrate, and a second conductive-type clad layer is disposed on the first conductive-type clad layer. An active layer is interposed between the first conductive-type clad layer and the second conductive-type clad layer. Column-shaped nano patterns are arranged at a surface of the second conductive-type clad layer to form a laser diode such as a distributed feedback laser diode.
    Type: Application
    Filed: April 27, 2010
    Publication date: August 19, 2010
    Applicants: Seoul Opto Device Co., Ltd., The University of Tokushima
    Inventor: Shiro SAKAI
  • Patent number: 7760784
    Abstract: A laser diode having nano patterns is disposed on a substrate. A first conductive-type clad layer is disposed on the substrate, and a second conductive-type clad layer is disposed on the first conductive-type clad layer. An active layer is interposed between the first conductive-type clad layer and the second conductive-type clad layer. Column-shaped nano patterns are arranged at a surface of the second conductive-type clad layer to form a laser diode such as a distributed feedback laser diode.
    Type: Grant
    Filed: August 5, 2008
    Date of Patent: July 20, 2010
    Assignees: Seoul Opto Device Co., Ltd., The University of Tokushima
    Inventor: Shiro Sakai
  • 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
  • Publication number: 20100102329
    Abstract: A light-emitting device operating on a high drive voltage and a small drive current. LEDs (1) are two-dimensionally formed on an insulating substrate (10) of e.g., sapphire monolithically and connected in series to form an LED array. Two such LED arrays are connected to electrodes (32) in inverse parallel. Air-bridge wiring (28) is formed between the LEDs (1) and between the LEDs (1) and electrodes (32). The LED arrays are arranged zigzag to form a plurality of LEDs (1) to produce a high drive voltage and a small drive current. Two LED arrays are connected in inverse parallel, and therefore an AC power supply can be used as the power supply.
    Type: Application
    Filed: January 5, 2010
    Publication date: April 29, 2010
    Applicant: Seoul Semiconductor Co., Ltd.
    Inventors: Shiro Sakai, Jin-Ping Ao, Yasuo Ono
  • Patent number: 7700940
    Abstract: An LED emitting light of wavelength mainly 375 nm or below. The LED includes a GaN layer (16), an n-clad layer (20), an AlInGaN buffer layer (22), a light emitting layer (24), a p-clad layer (26), a p-electrode (30), and an n-electrode (32) arranged on a substrate (10). The light emitting layer (24) has a multi-layer quantum well structure (MQW) in which an InGaN well layer and an AlInGaN barrier layer are superimposed. The quantum well structure increases the effective band gap of the InGaN well layer and reduces the light emitting wavelength. Moreover, by using the AlInGaN buffer layer (22) as the underlying layer of the light emitting layer (24), it is possible to effectively inject electrons into the light emitting layer (24), thereby increasing the light emitting efficiency.
    Type: Grant
    Filed: July 1, 2003
    Date of Patent: April 20, 2010
    Assignee: Nitride Semiconductor Co., Ltd.
    Inventors: Shiro Sakai, Tomoya Sugahara
  • Publication number: 20100091261
    Abstract: An operating valve of the present invention is a differential pressure operating valve 100 for performing a vacuum suction of a substrate, the operating valve comprises a body 4 having an opening which is provided at an exhaust side for exhausting an air from an inside to an outside and is opposed to a suction side for sucking the air from the outside to the inside, a valve 8, and a spring 9 whose one end is connected with one of the suction side and the exhaust side of the body 4 and the other end is connected with the valve 8. The spring 9 is configured to stretch or compress in accordance with a differential pressure between the suction side and the exhaust side, and the valve 8 is provided with at least one hole.
    Type: Application
    Filed: October 6, 2009
    Publication date: April 15, 2010
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Hiroyuki Eki, Shiro Sakai