Patents by Inventor Takashi Motoda

Takashi Motoda 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: 9041197
    Abstract: A semiconductor device includes a semiconductor element having a substrate of GaAs, InP, or GaN, and an element securing member bonded to the semiconductor element by solder. The element securing member is a composite material of Cu and carbon or a composite of Al and carbon. A stem is connected to the element securing member, and a cap is secured to the stem. The cap covers the semiconductor element and the element securing member. The stem and the element securing member are made of the same material.
    Type: Grant
    Filed: September 10, 2014
    Date of Patent: May 26, 2015
    Assignee: MITSUBISHI ELECTRIC CORPORATION
    Inventor: Takashi Motoda
  • Publication number: 20140374770
    Abstract: A semiconductor device includes a semiconductor element having a substrate of GaAs, InP, or GaN, and an element securing member bonded to the semiconductor element by solder. The element securing member is a composite material of Cu and carbon or a composite of Al and carbon. A stem is connected to the element securing member, and a cap is secured to the stem. The cap covers the semiconductor element and the element securing member. The stem and the element securing member are made of the same material.
    Type: Application
    Filed: September 10, 2014
    Publication date: December 25, 2014
    Inventor: Takashi Motoda
  • Patent number: 8855161
    Abstract: A semiconductor laser device includes a substrate, ridge stripes on the substrate and separated by separation sections, a top surface electrode continuously extending over the ridge stripes, and a bottom surface electrode on a bottom surface of the substrate. Each of the ridge stripes includes a lower cladding layer on the substrate, an active layer on the lower cladding layer, an upper cladding layer on the active layer, and a contact layer on the upper cladding layer.
    Type: Grant
    Filed: January 24, 2013
    Date of Patent: October 7, 2014
    Assignee: Mitsubishi Electric Corporation
    Inventor: Takashi Motoda
  • Publication number: 20130299843
    Abstract: A semiconductor device includes a semiconductor element having a substrate of GaAs, InP, or GaN, and an element securing member bonded to the semiconductor element by solder. The element securing member is a composite material of Cu and carbon or a composite of Al and carbon.
    Type: Application
    Filed: January 16, 2013
    Publication date: November 14, 2013
    Applicant: Mitsubishi Electric Corporation
    Inventor: Takashi Motoda
  • Patent number: 8563343
    Abstract: A method of manufacturing a laser diode device includes: forming, in a semiconductor laser bar, separation trenches extending across all of a transverse dimension of the semiconductor laser bar and defining a mesa stripe, each of the separation trenches having wide portions located at longitudinal edge portions of the semiconductor laser bar and a narrow portion located in a longitudinal central portion of the semiconductor laser bar; scribing, in the semiconductor laser bar, grooves extending parallel to the separation trenches and terminating before reaching longitudinal edge portions of the semiconductor laser bar; and splitting the semiconductor laser bar along the grooves to form cleaved surfaces extending from a bottom surface of the semiconductor laser bar to bottom surfaces of the separation trenches.
    Type: Grant
    Filed: May 17, 2012
    Date of Patent: October 22, 2013
    Assignee: Mitsubishi Electric Corporation
    Inventor: Takashi Motoda
  • Publication number: 20130243025
    Abstract: A semiconductor laser device includes a substrate, ridge stripes on the substrate and separated by separation sections, a top surface electrode continuously extending over the ridge stripes, and a bottom surface electrode on a bottom surface of the substrate. Each of the ridge stripes includes a lower cladding layer on the substrate, an active layer on the lower cladding layer, an upper cladding layer on the active layer, and a contact layer on the upper cladding layer.
    Type: Application
    Filed: January 24, 2013
    Publication date: September 19, 2013
    Applicant: Mitsubishi Electric Corporation
    Inventor: Takashi Motoda
  • Patent number: 8472495
    Abstract: A laser device includes a substrate, a lower cladding layer on the substrate, an active layer on the lower cladding layer and having a disordered portion spaced from an end face of a resonator of the laser device, an upper cladding layer located on the active layer, and a diffraction grating located in a portion of a layer lying above or below the active layer, with respect to the substrate. The disordered portion intersects a boundary between a diffraction grating section, in which the diffraction grating is located, and a bulk section, in which no diffraction grating is located.
    Type: Grant
    Filed: February 22, 2012
    Date of Patent: June 25, 2013
    Assignee: Mitsubishi Electric Corporation
    Inventor: Takashi Motoda
  • Publication number: 20130065334
    Abstract: A method of manufacturing a laser diode device includes: forming semiconductor layers on top of one another and supported by a top surface of a semiconductor substrate, the semiconductor layers including an active layer, forming a separation trench by etching and removing portions of the semiconductor layers, from a top semiconductor layer to and including the active layer; scribing a groove in a bottom surface of the semiconductor substrate, directly opposite and along the separation trench; and propagating a crack from the groove, splitting the semiconductor substrate along the groove and forming a cleaved surface extending from the bottom surface of the semiconductor substrate to a bottom surface of the separation trench.
    Type: Application
    Filed: May 17, 2012
    Publication date: March 14, 2013
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventor: Takashi MOTODA
  • Publication number: 20130065335
    Abstract: A method of manufacturing a laser diode device includes: forming, in a semiconductor laser bar, separation trenches extending across all of a transverse dimension of the semiconductor laser bar and defining a mesa stripe, each of the separation trenches having wide portions located at longitudinal edge portions of the semiconductor laser bar and a narrow portion located in a longitudinal central portion of the semiconductor laser bar; scribing, in the semiconductor laser bar, grooves extending parallel to the separation trenches and terminating before reaching longitudinal edge portions of the semiconductor laser bar; and splitting the semiconductor laser bar along the grooves to form cleaved surfaces extending from a bottom surface of the semiconductor laser bar to bottom surfaces of the separation trenches.
    Type: Application
    Filed: May 17, 2012
    Publication date: March 14, 2013
    Applicant: Mitsubishi Electric Corporation
    Inventor: Takashi MOTODA
  • Patent number: 8369372
    Abstract: A laser device includes a substrate, a lower cladding layer on the substrate, an active layer on the lower cladding layer, an upper cladding layer on the active layer, and a second order diffraction grating in a layer above the active layer and having dimensions of at least 100 ?m by 100 ?m. The second order diffraction grating diffracts and directs light generated in the active layer in a direction generally perpendicular to the longitudinal direction of the upper cladding layer. A laser device further includes a first reflective film on a first end face of a resonator, and a second reflective film on a second end face of the resonator, the second end face being located at the opposite end of the resonator to the first end face.
    Type: Grant
    Filed: March 21, 2012
    Date of Patent: February 5, 2013
    Assignee: Mitsubishi Electric Corporation
    Inventor: Takashi Motoda
  • Publication number: 20130028284
    Abstract: A laser device includes a substrate, a lower cladding layer on the substrate, an active layer on the lower cladding layer, an upper cladding layer on the active layer, and a second order diffraction grating in a layer above the active layer and having dimensions of at least 100 ?m by 100 ?m. The second order diffraction grating diffracts and directs light generated in the active layer in a direction generally perpendicular to the longitudinal direction of the upper cladding layer. A laser device further includes a first reflective film on a first end face of a resonator, and a second reflective film on a second end face of the resonator, the second end face being located at the opposite end of the resonator to the first end face.
    Type: Application
    Filed: March 21, 2012
    Publication date: January 31, 2013
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventor: Takashi MOTODA
  • Publication number: 20130016749
    Abstract: A surface emitting laser diode includes: a semiconductor substrate; a first semiconductor layer of a first conductivity type on the semiconductor substrate; an active layer on the first semiconductor layer; a second semiconductor layer of a second conductivity type on the active layer; and a second order diffraction grating in one of the first semiconductor layer and the second semiconductor layer. The second order diffraction grating has a pattern which includes concentric circles, a spiral, or polygons. An active region including the first semiconductor layer, the active layer, and the second semiconductor layer, is circular or polygonal.
    Type: Application
    Filed: February 16, 2012
    Publication date: January 17, 2013
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventor: Takashi MOTODA
  • Publication number: 20120320940
    Abstract: A laser device includes a substrate, a lower cladding layer on the substrate, an active layer on the lower cladding layer and having a disordered portion spaced from an end face of a resonator of the laser device, an upper cladding layer located on the active layer, and a diffraction grating located in a portion of a layer lying above or below the active layer, with respect to the substrate. The disordered portion intersects a boundary between a diffraction grating section, in which the diffraction grating is located, and a bulk section, in which no diffraction grating is located.
    Type: Application
    Filed: February 22, 2012
    Publication date: December 20, 2012
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventor: Takashi MOTODA
  • Publication number: 20070203936
    Abstract: A data-type expressing unit expresses, when a data type of a parameter for an application is out of a range of data type supported by an interface definition language, a predetermined data type of the interface definition language corresponding to the data type of the application in the interface definition language, based on information on the data type of the application. A file generating unit generates an interface-definition-language file in which information required for generating a broker program is expressed in the interface definition language using the data type of the interface definition language expressed by the data-type expressing unit.
    Type: Application
    Filed: May 15, 2006
    Publication date: August 30, 2007
    Inventors: Yoshitaka Honishi, Takashi Motoda, Atsushi Kitamura, Yasunari Tateiwa
  • Patent number: 5872022
    Abstract: A method of etching a III-V compound semiconductor uses an etching gas including the group V element of the III-V compound semiconductor substrate layer while keeping the III-V compound semiconductor layer at a temperature higher than the crystal growth temperature of the III-V compound semiconductor. Etching using this method provides a higher degree of controllability than wet etching. In addition, because no etching solution is employed, the etching method can be employed in a crystal growth apparatus. Further, because an element of the III-V compound semiconductor layer is employed in the etching gas, incorporation of residual impurities can be prevented, keeping the etched surface clean.
    Type: Grant
    Filed: September 1, 1995
    Date of Patent: February 16, 1999
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Takashi Motoda, Manabu Kato, Masayoshi Takemi
  • Patent number: 5768303
    Abstract: A semiconductor device includes a first conductivity type cladding layer; a second conductivity type cladding layer; an active layer of a semiconductor sandwiched between the first conductivity type cladding layer and the second conductivity type cladding layer; and a second conductivity type superlattice barrier layer sandwiched between the active layer and the second conductivity type cladding layer and having a superlattice structure including a first compound semiconductor having a larger energy band gap than the active layer and a second compound semiconductor having a smaller energy difference in the conduction band than the first compound semiconductor and a larger energy difference in the valence band than the first compound semiconductor, the first and second conductivity type compound semiconductors being alternatingly laminated in at least one pair of layers.
    Type: Grant
    Filed: February 6, 1997
    Date of Patent: June 16, 1998
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Takashi Motoda, Kenichi Ono
  • Patent number: 5763291
    Abstract: A method of fabricating a semiconductor laser producing visible light includes forming a double heterojunction (DH) structure on a GaAs substrate including an n type GaAs buffer layer, an n type AlGaInP cladding layer, an Al.sub.x Ga.sub.(1-x) InP active layer, a first p type AlGaInP cladding layer, a p type GaInP etch stopping layer, a second p type AlGaInP cladding layer, and a p type GaAs cap layer. A stripe-shaped mask is formed on the DH structure, the p type GaAs cap layer is selectively etched using the mask, and the second p type AlGaInP cladding layer is selectively etched to the p type GaInP etch stopping layer to form a stripe-shaped ridge. Therefore, a high precision ridge can be formed easily.
    Type: Grant
    Filed: September 1, 1995
    Date of Patent: June 9, 1998
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Takashi Motoda, Manabu Kato
  • Patent number: 5741359
    Abstract: An apparatus for zone-melting recrystallization of a semiconductor layer includes a first heater, on which a semiconductor wafer including the semiconductor layer and upper and lower insulating films sandwiching the semiconductor layer is mounted, for radiantly heating a rear surface of the semiconductor wafer to a temperature at which the semiconductor layer and the insulating layers are not melted; and a second heater disposed above the semiconductor wafer and radiantly heating a front surface of the semiconductor wafer. The second heater has a heat generating point that produces a heated spot in the semiconductor layer and moves spirally while maintaining a fixed distance from the semiconductor wafer, thereby producing a large-area monocrystalline region in the semiconductor layer. In this zone-melting recrystallization, a single crystalline nucleus is produced in the semiconductor layer, and the entire semiconductor layer is recrystallized with the crystalline nucleus as a seed crystal.
    Type: Grant
    Filed: September 7, 1995
    Date of Patent: April 21, 1998
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Takashi Motoda, Manabu Kato
  • Patent number: 5737350
    Abstract: A multi-quantum barrier layer includes alternatingly laminated barrier layers of a III-V compound semiconductor material and well layers of a III-V compound semiconductor material including the same Group V element as in the barrier layers. During the formation of the multi-quantum barrier layer it is not necessary to switch the Group V element source gas at the interface between a barrier layer and a well layer so that this interface is abrupt, improving the electron reflection efficiency of the multi-quantum barrier layer.
    Type: Grant
    Filed: September 18, 1995
    Date of Patent: April 7, 1998
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Takashi Motoda, Manabu Kato
  • Patent number: 5734670
    Abstract: A semiconductor device includes a semiconductor substrate having a surface; and a strained superlattice structure including first semiconductor layers having a first strain in a direction with respect to the semiconductor substrate and second semiconductor layers having a second strain in the same direction as and different in magnitude from the first strain, the first semiconductor layers and the second semiconductor layers being alternatingly laminated. The difference in strains between the first semiconductor layers and the second semiconductor layers is reduced, so that the crystalline quality of the strained superlattice structure is improved.
    Type: Grant
    Filed: April 15, 1996
    Date of Patent: March 31, 1998
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Kenichi Ono, Takashi Motoda