Patents by Inventor Tomoji Yamaguchi

Tomoji Yamaguchi 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: 20080042150
    Abstract: There are provided a white light emitting device of high luminous efficiency prevented from luminance deterioration even in large electric current range, and a method for manufacturing the same with high production yield. The white light emitting device (1) is composed of a blue LED element (4) and an oxide layer (8) containing a fluorescent material which is integrated with the blue LED element (4). In the blue LED element (4), a p-side electrode (11) is formed on a surface of a p-type layer of epitaxial layers (6) formed by laminating GaN based compound semiconductor layers on a surface of a light transmitting crystal substrate (3), and an n-side electrode (10) is formed on a bottom surface of a recessed portion (9) which is an n-type layer exposed by selectively etching a part of the p-type layer and the light emitting layer. The oxide layer (8) is formed by sintering a YAG fluorescent material and a glass binder containing mainly SiO2, B2O3 and PbO for binding the fluorescent material.
    Type: Application
    Filed: June 22, 2005
    Publication date: February 21, 2008
    Inventor: Tomoji Yamaguchi
  • Publication number: 20070246731
    Abstract: A semiconductor device includes an insulating substrate 2 having an obverse surface formed with a die pad 3, a rectangular semiconductor chip 7 such as an LED chip bonded to the die pad with a die bonding material 10, and a molded portion 9 made of a synthetic resin for packaging the semiconductor chip. The die pad 3 may be rectangular with dimensions close to those of the semiconductor chip or circular with a diameter close to the diagonal dimension of the semiconductor chip, whereby the positioning and orienting of the semiconductor chip can be accurately performed in bonding the semiconductor chip.
    Type: Application
    Filed: June 7, 2007
    Publication date: October 25, 2007
    Applicant: ROHM CO., LTD.
    Inventors: Shinji Isokawa, Tomoji Yamaguchi
  • Patent number: 7242033
    Abstract: A semiconductor device includes an insulating substrate 2 having an obverse surface formed with a die pad 3, a rectangular semiconductor chip 7 such as an LED chip bonded to the die pad with a die bonding material 10, and a molded portion 9 made of a synthetic resin for packaging the semiconductor chip. The die pad 3 may be rectangular with dimensions close to those of the semiconductor chip or circular with a diameter close to the diagonal dimension of the semiconductor chip, whereby the positioning and orienting of the semiconductor chip can be accurately performed in bonding the semiconductor chip.
    Type: Grant
    Filed: February 24, 2003
    Date of Patent: July 10, 2007
    Assignee: Rohm Co., Ltd.
    Inventors: Shinji Isokawa, Tomoji Yamaguchi
  • Patent number: 7128444
    Abstract: A light emitting diode lamp includes a lead terminal 2 formed with a cup 8 having a conical inner circumferential surface serving as a light reflective surface 8a, an LED chip 4 bonded to a bottom surface 8b of the cup with a die bonding material H, a molded portion 6 made of a transparent synthetic resin for packaging the cup of the lead terminal. The bottom surface 8b of the cup is formed with a recess 9 or a protrusion 19 to which the LED chip 4 is bonded with the die bonding material H, whereby the light conversion efficiency of the conical light reflective surface 8a is enhanced.
    Type: Grant
    Filed: February 24, 2003
    Date of Patent: October 31, 2006
    Assignee: Rohm Co., Ltd.
    Inventors: Shinji Isokawa, Tomoji Yamaguchi
  • Publication number: 20050156187
    Abstract: A semiconductor device includes an insulating substrate 2 having an obverse surface formed with a die pad 3, a rectangular semiconductor chip 7 such as an LED chip bonded to the die pad with a die bonding material 10, and a molded portion 9 made of a synthetic resin for packaging the semiconductor chip. The die pad 3 may be rectangular with dimensions close to those of the semiconductor chip or circular with a diameter close to the diagonal dimension of the semiconductor chip, whereby the positioning and orienting of the semiconductor chip can be accurately performed in bonding the semiconductor chip.
    Type: Application
    Filed: February 24, 2003
    Publication date: July 21, 2005
    Inventors: Shinji Isokawa, Tomoji Yamaguchi
  • Publication number: 20050116246
    Abstract: A light emitting diode lamp includes a lead terminal 2 formed with a cup 8 having a conical inner circumferential surface serving as a light reflective surface 8a, an LED chip 4 bonded to a bottom surface 8b of the cup with a die bonding material H, a molded portion 6 made of a transparent synthetic resin for packaging the cup of the lead terminal. The bottom surface 8b of the cup is formed with a recess 9 or a protrusion 19 to which the LED chip 4 is bonded with the die bonding material H, whereby the light conversion efficiency of the conical light reflective surface 8a is enhanced.
    Type: Application
    Filed: February 24, 2003
    Publication date: June 2, 2005
    Applicant: ROHM CO. LTD.
    Inventors: Shinji Isokawa, Tomoji Yamaguchi
  • Patent number: 6392294
    Abstract: A semiconductor device is provided which includes an insulating substrate, a conductive terminal supported by the substrate, a semiconductor chip mounted on the substrate, and a protection coating for enclosing the chip. The protection coating is integrally formed with an anchoring portion. The substrate is formed with an engaging portion for engagement with the anchoring portion of the coating.
    Type: Grant
    Filed: December 15, 1999
    Date of Patent: May 21, 2002
    Assignee: Rohm Co., Ltd.
    Inventor: Tomoji Yamaguchi
  • Patent number: 5564819
    Abstract: An LED lamp has a first lead formed with a reflecting plate at an upper end and a pair of further leads spaced on opposite sides of the first lead, and a plurality of LED chips mounted in linear spaced relation on the reflecting plate. The direction Y of the spacing of the plurality of LED chips is inclined at a predetermined angle .alpha. to the spacing direction X of the leads. The reflecting plate has an elongated shape and the plurality of LED chips are spaced in the direction of elongation of the reflecting plate.
    Type: Grant
    Filed: March 28, 1995
    Date of Patent: October 15, 1996
    Assignee: Rohm Co., Ltd.
    Inventor: Tomoji Yamaguchi