Patents by Inventor Toshinari Fujimori

Toshinari Fujimori 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: 7164157
    Abstract: A light emitting device including a substrate transparent at the emission wavelength and an active layer structure formed on such substrate, in which the thickness of the substrate is 75 ?m or less, and/or a layer for suppressing spectral-intensity-modulation due to the substrate-mode is provided between the substrate and the active layer structure. Such device can suppress the spectral-intensity-modulation due to the substrate-mode, which is observed for the case the substrate is transparent at the emission wavelength, to thereby provide a light emission device excellent in linearity of the current-light output characteristics, and to thereby improve the coupling characteristics with an external cavity.
    Type: Grant
    Filed: October 20, 2005
    Date of Patent: January 16, 2007
    Assignee: Mitsubishi Chemical Corporation
    Inventors: Horie Hideyoshi, Satoru Nagao, Yoshitaka Yamamoto, Toshinari Fujimori
  • Patent number: 7102174
    Abstract: The present invention discloses a light emitting device comprising a substrate transparent at the emission wavelength and an active layer structure formed on such substrate, in which the thickness of the substrate is 75 ?m or less, and/or a layer for suppressing spectral-intensity-modulation due to the substrate-mode is provided between the substrate and the active layer structure. Such device can suppress the spectral-intensity modulation due to the substrate-mode, which is observed for the case the substrate is transparent at the emission wavelength, to thereby provide a light emission device excellent in linearity of the current-light output characteristics, and to thereby improve the coupling characteristics with an external cavity.
    Type: Grant
    Filed: May 21, 2001
    Date of Patent: September 5, 2006
    Assignee: Mitsubishi Chemical Corporation
    Inventors: Horie Hideyoshi, Satoru Nagao, Yoshitaka Yamamoto, Toshinari Fujimori
  • Publication number: 20060038185
    Abstract: A light emitting device including a substrate transparent at the emission wavelength and an active layer structure formed on such substrate, in which the thickness of the substrate is 75 ?m or less, and/or a layer for suppressing spectral-intensity-modulation due to the substrate-mode is provided between the substrate and the active layer structure. Such device can suppress the spectral-intensity-modulation due to the substrate-mode, which is observed for the case the substrate is transparent at the emission wavelength, to thereby provide a light emission device excellent in linearity of the current-light output characteristics, and to thereby improve the coupling characteristics with an external cavity.
    Type: Application
    Filed: October 20, 2005
    Publication date: February 23, 2006
    Applicant: MITSUBISHI CHEMICAL CORPORATION
    Inventors: Hideyoshi Horie, Satoru Nagao, Yoshitaka Yamamoto, Toshinari Fujimori
  • Patent number: 6744074
    Abstract: Compound semiconductor light emitting devices capable of suppressing the surface state density on the facets of semiconductor light emitting devices such as semiconductor lasers for a long time and stable operating even when the passivation layer diffuses can be easily obtained. Compound semiconductor light emitting devices with an emission wavelength of &lgr; (nm) wherein a first conduction type of clad layer, an active layer and a second conduction type of clad layer are grown on a substrate and two facets are opposite to each other so as to form a cavity, characterized in that said active layer is transparent to the emission wavelength in the vicinities of the facets and that the surfaces of the first conduction type of clad layer, active layer and second conduction type of clad layer forming said facets are each coated with a passivation layer.
    Type: Grant
    Filed: October 3, 2001
    Date of Patent: June 1, 2004
    Assignee: Mitsubishi Chemical Corporation
    Inventors: Hideyoshi Horie, Hirotaka Ohta, Toshinari Fujimori
  • Patent number: 6677618
    Abstract: Disclosed compound semiconductor light emitting devices have a substrate, a compound semiconductor layer, formed on the substrate, containing a first conductive type clad layer, an active layer, and a second conductive type clad layer, and a resonator structure formed of two opposing facets of the compound semiconductor layer, wherein surfaces of the first conductive type clad layer, the active layer, and the second conductive type clad layer forming the facet of the compound semiconductor are covered with a passivation layer, wherein at least one element constituting the facet of the compound semiconductor layer is not coupled to oxygen, and wherein a portion of the passivation layer adjacent to the facet of the compound semiconductor layer contains oxygen as a structural element.
    Type: Grant
    Filed: December 3, 1999
    Date of Patent: January 13, 2004
    Assignee: Mitsubishi Chemical Corporation
    Inventors: Hideyoshi Horie, Hirotaka Ohta, Toshinari Fujimori
  • Publication number: 20020020847
    Abstract: Compound semiconductor light emitting devices capable of suppressing the surface state density on the facets of semiconductor light emitting devices such as semiconductor lasers for a long time and stable operating even when the passivation layer diffuses can be easily obtained. Compound semiconductor light emitting devices with an emission wavelength of &lgr; (nm) wherein a first conduction type of clad layer, an active layer and a second conduction type of clad layer are grown on a substrate and two facets are opposite to each other so as to form a cavity, characterized in that said active layer is transparent to the emission wavelength in the vicinities of the facets and that the surfaces of the first conduction type of clad layer, active layer and second conduction type of clad layer forming said facets are each coated with a passivation layer.
    Type: Application
    Filed: October 3, 2001
    Publication date: February 21, 2002
    Applicant: MITSUBISHU CHEMICAL CORPORATION
    Inventors: Hideyoshi Horie, Hirotaka Ohta, Toshinari Fujimori
  • Publication number: 20020014674
    Abstract: The present invention discloses a light emitting device comprising a substrate transparent at the emission wavelength and an active layer structure formed on such substrate, in which the thickness of the substrate is 75 &mgr;m or less, and/or a layer for suppressing spectral-intensity-modulation due to the substrate-mode is provided between the substrate and the active layer structure. Such device can suppress the spectral-intensity modulation due to the substrate-mode, which is observed for the case the substrate is transparent at the emission wavelength, to thereby provide a light emission device excellent in linearity of the current-light output characteristics, and to thereby improve the coupling characteristics with an external cavity.
    Type: Application
    Filed: May 21, 2001
    Publication date: February 7, 2002
    Inventors: Horie Hideyoshi, Satoru Nagao, Yoshitaka Yamamoto, Toshinari Fujimori
  • Patent number: 6323052
    Abstract: Compound semiconductor light emitting devices capable of suppressing the surface state density on the facets of semiconductor light emitting devices such as semiconductor lasers for a long time and stable operating even when the passivation layer diffuses can be easily obtained. Compound semiconductor light emitting devices with an emission wavelength of &lgr; (nm) wherein a first conduction type of clad layer, an active layer and a second conduction type of clad layer are grown on a substrate and two facets are opposite to each other so as to form a cavity, characterized in that said active layer is transparent to the emission wavelength in the vicinities of the facets and that the surfaces of the first conduction type of clad layer, active layer and second conduction type of clad layer forming said facets are each coated with a passivation layer.
    Type: Grant
    Filed: June 11, 1998
    Date of Patent: November 27, 2001
    Assignee: Mitsubishi Chemical Corporation
    Inventors: Hideyoshi Horie, Hirotaka Ohta, Toshinari Fujimori
  • Patent number: 6172998
    Abstract: The present invention relates to a semiconductor laser diode comprising a GaAs substrate and at least a first conduction-type clad layer, an active layer containing In, Ga and As as component elements, a second conduction-type first clad layer, a current block layer and a second conduction-type second clad layer which are deposited on the substrate in order, wherein a current injection region is formed by said current block layer and said second conduction-type second clad layer, the effective refractive index step &Dgr;neff in the horizontal direction is from 2.5×10−3 to 5.0×10−3 at the emission wavelength, and the width W of the current injection region is from 1.5 to 2.5 &mgr;m. The semiconductor laser diode of the present invention is suited for uses where high output and long life-time are required, such as excitation light source for optical fiber amplifiers.
    Type: Grant
    Filed: November 17, 1997
    Date of Patent: January 9, 2001
    Assignee: Mitsubishi Chemical Corporation
    Inventors: Hideyoshi Horie, Toshinari Fujimori, Satoru Nagao, Hideki Goto
  • Patent number: 5920767
    Abstract: The disclosure describes a method of forming a groove in a structure of a semiconductor laser diode, which comprises a crystal growth procedure of epitaxial growth of a core layer comprising MP, wherein M represents one or more of elements belonging to group IIIb of periodic table and an upper layer comprising MAs, wherein M represents one or more of elements belonging to group IIIb of periodic table, successively on (100) surface of MAs crystals in a lower layer comprising MAs; a photolithography and wet etching procedure of, after forming an etching mask on the upper layer, forming an etching window to the etching mask; a first etching procedure of selective etching the upper layer; and a second etching procedure of selective etching other faces except for the face in which (111) face of MP crystals in the core layer is exposed.
    Type: Grant
    Filed: July 22, 1996
    Date of Patent: July 6, 1999
    Assignee: Mitsubishi Chemical Company
    Inventors: Hideyoshi Horie, Toshinari Fujimori, Satoru Nagao, Nobuyuki Hosoi, Hideki Goto
  • Patent number: 5868834
    Abstract: The disclosure describes a method of manufacturing a Group II-VI compound semiconductor thin film by a vapor-phase epitaxy using an organic metal compound of Group II element and a hydride or an organic metal compound of Group VI element as the raw material, which comprises repeating alternate introduction of an organic metal compound of Group II element and a halide gas, a halogen gas or a mixture thereof; or adding a halide gas, a halogen gas or a mixture thereof to a gas for vapor-phase epitaxy.
    Type: Grant
    Filed: June 16, 1997
    Date of Patent: February 9, 1999
    Assignee: Mitsubishi Kasei Corporation
    Inventors: Kenji Shimoyama, Toshinari Fujimori, Hideki Goto
  • Patent number: 5838028
    Abstract: The invention provides a semiconductor device having a structure wherein a layer comprising at least Al.sub.W Ga.sub.1-W As is formed on a substrate and a second etching stop layer, a first etching stop layer and a layer comprising Al.sub.Y Ga.sub.1-Y As are deposited on the layer comprising Al.sub.W Ga.sub.1-W As in the described order, with a portion of the layer comprising Al.sub.Y G.sub.1-Y As and a portion of the first etching stop layer being removed. This structure enables a desired ridge shape to be fabricated with good quality and allows for free selection of the Al mixed crystal ratio of the layer to be etched, and makes it possible to form the re-growth interface of GaAs. Thus, the qualty of crystal of the re-grown portion can be improved.
    Type: Grant
    Filed: May 22, 1997
    Date of Patent: November 17, 1998
    Assignee: Mitsubishi Chemical Corporation
    Inventors: Hideyoshi Horie, Toshinari Fujimori, Satoru Nagao, Hideki Gotoh
  • Patent number: 5608751
    Abstract: The disclosure describes a laser diode comprising a Group III-V compound single-crystal substrate of first conduction type; a first cladding layer of first conduction type composed of (Al.sub.m Ga.sub.1-m).sub.n In.sub.1-n P (0.3.ltoreq.m.ltoreq.1 and 0.3.ltoreq.n.ltoreq.0.75) and formed on said single-crystal substrate; an active layer composed of (Al.sub.x Ga.sub.1-x).sub.y In.sub.1-y P (0.ltoreq.x.ltoreq.0.5 and 0.3.ltoreq.y.ltoreq.0.75) and formed on said first cladding layer; a second cladding layer of second conduction type composed of (Al.sub.m Ga.sub.1-m).sub.n In.sub.1-n P (0.3.ltoreq.m.ltoreq.1 and 0.3.ltoreq.n.ltoreq.0.75) and formed on said active layer and having a ridge; and a current blocking layer composed of Al.sub.u Ga.sub.1-u As.sub.v P.sub.1-v, (0.ltoreq.u.ltoreq.1 and 0.ltoreq.v.ltoreq.
    Type: Grant
    Filed: March 14, 1994
    Date of Patent: March 4, 1997
    Assignee: Mitsubishi Chemical Corporation
    Inventors: Kenji Shimoyama, Toshinari Fujimori, Satoru Nagao, Hideki Gotoh
  • Patent number: 5566198
    Abstract: The disclosure describes a method of forming a groove in a structure of a semiconductor laser diode, which comprises a crystal growth procedure of epitaxial growth of a core layer comprising MP, wherein M represents one or more of elements belonging to group IIIb of periodic table and an upper layer comprising MAs, wherein M represents one or more of elements belonging to group IIIb of periodic table, successively on (100) surface of MAs crystals in a lower layer comprising MAs; a photolithography and wet etching procedure of, after forming an etching mask on the upper layer, forming an etching window to the etching mask; a first etching procedure of selective etching the upper layer; and a second etching procedure of selective etching other faces except for the face in which (111) face of MP crystals in the core layer is exposed.
    Type: Grant
    Filed: January 30, 1995
    Date of Patent: October 15, 1996
    Assignee: Mitsubishi Chemical Corporation
    Inventors: Hideyoshi Horie, Toshinari Fujimori, Satoru Nagao, Nobuyuki Hosoi, Hideki Goto