Patents by Inventor Masaki Ueno

Masaki Ueno 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: 8415707
    Abstract: A Group III nitride semiconductor device has a semiconductor region, a metal electrode, and a transition layer. The semiconductor region has a surface comprised of a Group III nitride crystal. The semiconductor region is doped with a p-type dopant. The surface is one of a semipolar surface and a nonpolar surface. The metal electrode is provided on the surface. The transition layer is formed between the Group III nitride crystal of the semiconductor region and the metal electrode. The transition layer is made by interdiffusion of a metal of the metal electrode and a Group III nitride of the semiconductor region.
    Type: Grant
    Filed: July 13, 2010
    Date of Patent: April 9, 2013
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Shinji Tokuyama, Masaki Ueno, Masahiro Adachi, Takashi Kyono, Takamichi Sumitomo, Koji Katayama, Yoshihiro Saito
  • Patent number: 8405066
    Abstract: A nitride-based semiconductor light-emitting device having enhanced efficiency of carrier injection to a well layer is provided. The nitride-based semiconductor light-emitting device comprises a hexagonal gallium nitride-based semiconductor substrate 5, an n-type gallium nitride-based semiconductor region 7 disposed on the principal surface S1 of the substrate 5, a light-emitting layer 11 having a single-quantum-well structure disposed on the n-type gallium nitride-based semiconductor region 7, and a p-type gallium nitride-based semiconductor region 19 disposed on the light-emitting layer 11. The light-emitting layer 11 is disposed between the n-type gallium nitride-based semiconductor region 7 and the p-type gallium nitride-based semiconductor region 19. The light-emitting layer 11 includes a well layer 15 and barrier layers 13 and 17. The well layer 15 comprises InGaN.
    Type: Grant
    Filed: June 14, 2010
    Date of Patent: March 26, 2013
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Takashi Kyono, Yohei Enya, Yusuke Yoshizumi, Katsushi Akita, Takamichi Sumitomo, Masaki Ueno
  • Patent number: 8401048
    Abstract: In a III-nitride semiconductor laser device, a laser structure includes a support base comprised of a hexagonal III-nitride semiconductor and having a semipolar primary surface, and a semiconductor region provided on the semipolar primary surface of the support base. An electrode is provided on the semiconductor region of the laser structure. The c-axis of the hexagonal III-nitride semiconductor of the support base is inclined at an angle ALPHA with respect to a normal axis toward the m-axis of the hexagonal III-nitride semiconductor. The angle ALPHA is in the range of not less than 45 degrees and not more than 80 degrees or in the range of not less than 100 degrees and not more than 135 degrees. The laser structure includes first and second fractured faces that intersect with an m-n plane defined by the m-axis of the hexagonal III-nitride semiconductor and the normal axis. A laser cavity of the III-nitride semiconductor laser device includes the first and second fractured faces.
    Type: Grant
    Filed: July 15, 2010
    Date of Patent: March 19, 2013
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Shimpei Takagi, Yusuke Yoshizumi, Koji Katayama, Masaki Ueno, Takatoshi Ikegami
  • Patent number: 8391327
    Abstract: A primary surface 23a of a supporting base 23 of a light-emitting diode 21a tilts by an off-angle of 10 degrees or more and less than 80 degrees from the c-plane. A semiconductor stack 25a includes an active layer having an emission peak in a wavelength range from 400 nm to 550 nm. The tilt angle “A” between the (0001) plane (the reference plane SR3 shown in FIG. 5) of the GaN supporting base and the (0001) plane of a buffer layer 33a is 0.05 degree or more and 2 degrees or less. The tilt angle “B” between the (0001) plane of the GaN supporting base (the reference plane SR4 shown in FIG. 5) and the (0001) plane of a well layer 37a is 0.05 degree or more and 2 degrees or less. The tilt angles “A” and “B” are formed in respective directions opposite to each other with reference to the c-plane of the GaN supporting base.
    Type: Grant
    Filed: January 4, 2012
    Date of Patent: March 5, 2013
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Yusuke Yoshizumi, Yohei Enya, Masaki Ueno, Fumitake Nakanishi
  • Patent number: 8389312
    Abstract: A method of fabricating a group-III nitride semiconductor laser device includes: preparing a substrate of a hexagonal group-III nitride semiconductor, where the substrate has a semipolar primary surface; forming a substrate product having a laser structure, an anode electrode and a cathode electrode, where the laser structure includes the substrate and a semiconductor region, and where the semiconductor region is formed on the semipolar primary surface; scribing a first surface of the substrate product in part in a direction of the a-axis of the hexagonal group-III nitride semiconductor; and carrying out breakup of the substrate product by press against a second surface of the substrate product, to form another substrate product and a laser bar.
    Type: Grant
    Filed: February 7, 2012
    Date of Patent: March 5, 2013
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Yusuke Yoshizumi, Shimpei Takagi, Takatoshi Ikegami, Masaki Ueno, Koji Katayama
  • Publication number: 20130051417
    Abstract: A group III nitride semiconductor laser device includes a laser structure, an insulating layer, an electrode and dielectric multilayers. The laser structure includes a semiconductor region on a semi-polar primary surface of a hexagonal group III nitride semiconductor support base. The dielectric multilayers are on first and second end-faces for the laser cavity. The c-axis of the group III nitride tilts by an angle ALPHA from the normal axis of the primary surface in the waveguide axis direction from the first end-face to the second end-faces. A pad electrode has first to third portions provided on the first to third regions of the semiconductor regions, respectively. An ohmic electrode is in contact with the third region through an opening of the insulating layer. The first portion has a first arm, which extends to the first end-face edge. The third portion is away from the first end-face edge.
    Type: Application
    Filed: April 23, 2012
    Publication date: February 28, 2013
    Applicants: SONY CORPORATION, SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Takamichi SUMITOMO, Takashi KYONO, Masaki UENO, Yusuke YOSHIZUMI, Yohei ENYA, Masahiro ADACHI, Shimpei TAKAGI, Katsunori YANASHIMA
  • Publication number: 20130051418
    Abstract: A group-III nitride semiconductor laser device includes an n-type nitride semiconductor region, an active layer provided over the n-type nitride semiconductor region, a first p-type nitride semiconductor region provided over the active layer, a current confinement layer which is provided over the first p-type nitride semiconductor region and has an opening extending in a optical cavity direction, and a second p-type nitride semiconductor region re-grown on the first nitride semiconductor region and the current confinement layer after the formation of the opening of the current confinement layer. The interface between the first p-type nitride semiconductor region and the second p-type nitride semiconductor region includes a semi-polar plane. At least one of the first or second p-type semiconductor regions includes a highly doped p-type semiconductor layer forming an interface with the first and second p-type semiconductor regions and have a p-type impurity level of 1×1020 cm?3 or greater.
    Type: Application
    Filed: July 24, 2012
    Publication date: February 28, 2013
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Takamichi SUMITOMO, Masaki UENO, Yusuke YOSHIZUMI, Takahisa YOSHIDA, Masahiro ADACHI
  • Patent number: 8361885
    Abstract: A method of fabricating group-III nitride semiconductor laser device includes: preparing a substrate comprising a hexagonal group-III nitride semiconductor and having a semipolar principal surface; forming a substrate product having a laser structure, an anode electrode, and a cathode electrode, where the laser structure includes a semiconductor region and the substrate, where the semiconductor region is formed on the semipolar principal surface; scribing a first surface of the substrate product in a direction of an a-axis of the hexagonal group-III nitride semiconductor to form first and second scribed grooves; and carrying out breakup of the substrate product by press against a second surface of the substrate product, to form another substrate product and a laser bar.
    Type: Grant
    Filed: November 18, 2011
    Date of Patent: January 29, 2013
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Yusuke Yoshizumi, Shimpei Takagi, Takatoshi Ikegami, Masaki Ueno, Koji Katayama
  • Patent number: 8357946
    Abstract: Provided is a nitride semiconductor light emitting device including a light emitting layer above a GaN support base with a semipolar surface and allowing for suppression of reduction in luminous efficiency due to misfit dislocations. A nitride semiconductor light emitting device 11 has a support base 13 comprised of a hexagonal gallium nitride, an n-type gallium nitride-based semiconductor layer 15 including an InX1AlY1Ga1-X1-Y1N (0<X1<1, 0<Y1<1, X1+Y1<1) layer 21, a light emitting layer 17, and a p-type gallium nitride-based semiconductor layer 19. This InAlGaN layer 21 is provided between a semipolar primary surface 13a and the light emitting layer 17. Since the bandgap E of the InAlGaN layer 21 is not less than the bandgap E of gallium nitride, a confinement effect of carriers and light in the light emitting layer 17 is provided.
    Type: Grant
    Filed: July 22, 2011
    Date of Patent: January 22, 2013
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Takashi Kyono, Yusuke Yoshizumi, Yohei Enya, Katsushi Akita, Masaki Ueno, Takamichi Sumitomo
  • Patent number: 8357558
    Abstract: A method of making a semiconductor light-emitting device involves the steps of selecting at least one tilt angle for a primary surface of a substrate to evaluate the direction of piezoelectric polarization in a light-emitting layer, the substrate comprising a group III nitride semiconductor; preparing a substrate having the primary surface, the primary surface having the selected tilt angle, and the primary surface comprising the group III nitride semiconductor; forming a quantum well structure and p- and n-type gallium nitride semiconductor layers for the light-emitting layer at the selected tilt angle to prepare a substrate product; measuring photoluminescence of the substrate product while applying a bias to the substrate product, to determine bias dependence of the photoluminescence; evaluating the direction of the piezoelectric polarization in the light-emitting layer at the selected tilt angle on the primary surface of the substrate by the determined bias dependence; determining which of the primary sur
    Type: Grant
    Filed: July 15, 2010
    Date of Patent: January 22, 2013
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Takashi Kyono, Yohei Enya, Yusuke Yoshizumi, Katsushi Akita, Masaki Ueno, Takamichi Sumitomo, Masahiro Adachi, Shinji Tokuyama
  • Publication number: 20130009202
    Abstract: A group-III nitride semiconductor device includes a light emitting layer emitting light of a wavelength in the range of 480 to 600 nm; a first contact layer over the light emitting layer; a second contact layer in direct contact with the first contact layer; and a metal electrode in direct contact with the second contact layer. The first and second contact layers comprise a p-type gallium nitride-based semiconductor. The p-type dopant concentration of the first contact layer is lower than that of the second contact layer. The light emitting layer comprises a gallium nitride-based semiconductor. The interface between the first and second contact layers tilts at an angle of not less than 50 degrees and smaller than 130 degrees from a plane orthogonal to a reference axis extending along the c-axis. The second contact layer has a thickness within the range of 1 to 50 nm.
    Type: Application
    Filed: June 29, 2012
    Publication date: January 10, 2013
    Applicants: SONY CORPORATION, SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Yohei ENYA, Yusuke YOSHIZUMI, Takashi KYONO, Takamichi SUMITOMO, Masaki UENO, Katsunori YANASHIMA, Kunihiko TASAI, Hiroshi NAKAJIMA
  • Patent number: 8349083
    Abstract: A vapor-phase process apparatus and a vapor-phase process method capable of satisfactorily maintaining quality of processes even when different types of processes are performed are obtained. A vapor-phase process apparatus includes a process chamber, gas supply ports serving as a plurality of gas introduction portions, and a gas supply portion (a gas supply member, a pipe, a flow rate control device, a pipe, and a buffer chamber). The process chamber allows flow of a reaction gas therein. The plurality of gas supply ports are formed in a wall surface (upper wall) of the process chamber along a direction of flow of the reaction gas. The gas supply portion can supply a gas into the process chamber at a different flow rate from each of one gas supply port and another gas supply port different from that one gas supply port among the plurality of gas supply ports.
    Type: Grant
    Filed: October 11, 2011
    Date of Patent: January 8, 2013
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Eiryo Takasuka, Toshio Ueda, Toshiyuki Kuramoto, Masaki Ueno
  • Patent number: 8349403
    Abstract: A vapor-phase process apparatus and a vapor-phase process method capable of satisfactorily maintaining quality of processes even when different types of processes are performed are obtained. A vapor-phase process apparatus includes a process chamber, gas supply ports serving as a plurality of gas introduction portions, and a gas supply portion (a gas supply member, a pipe, a flow rate control device, a pipe, and a buffer chamber). The process chamber allows flow of a reaction gas therein. The plurality of gas supply ports are formed in a wall surface (upper wall) of the process chamber along a direction of flow of the reaction gas. The gas supply portion can supply a gas into the process chamber at a different flow rate from each of one gas supply port and another gas supply port different from that one gas supply port among the plurality of gas supply ports.
    Type: Grant
    Filed: September 13, 2011
    Date of Patent: January 8, 2013
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Eiryo Takasuka, Toshio Ueda, Toshiyuki Kuramoto, Masaki Ueno
  • Publication number: 20130003769
    Abstract: A gallium nitride-based semiconductor laser device with reduced threshold current. The gallium nitride-based semiconductor laser device is provided with an n-type cladding layer, an n-side light guide layer, an active layer, a p-side light guide layer, and a p-type cladding layer. The n-side light guide layer and the p-side light guide layer both contain indium. Each of indium compositions of the n-side light guide layer and the p-side light guide layer is not less than 2% and not more than 6%. A film thickness of the n-type cladding layer is in the range of not less than 65% and not more than 85% of a total of the film thickness of the n-type cladding layer and a film thickness of the p-type cladding layer 23.
    Type: Application
    Filed: March 27, 2012
    Publication date: January 3, 2013
    Applicants: SONY CORPORATION, SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Tetsuya Kumano, Masaki Ueno, Takashi Kyono, Yohei Enya, Katsunori Yanashima, Kunihiko Tasai, Hiroshi Nakajima
  • Publication number: 20120327967
    Abstract: A nitride semiconductor laser device includes a p-type cladding layer, an active layer and an n-type cladding layer. The p-type cladding layer and the n-type cladding layer comprise indium and aluminum as group-III constituent. The n-type cladding layer, active layer and p-type cladding layer are arranged along the normal of a semi-polar semiconductor surface of a substrate. This surface tilts toward the m-axis of the hexagonal nitride by an angle of 63 degrees or more and smaller than 80 degrees from a plane orthogonal to a reference axis extending along the c-axis thereof. The active layer generates light having a peak wavelength in the range of 480 to 600 nm. The refractive indices of the n-type cladding layer and p-type cladding layer are smaller than that of GaN. The n-type cladding layer has a thickness of 2 ?m or more while the p-type cladding layer has a thickness of 500 nm or more.
    Type: Application
    Filed: May 24, 2012
    Publication date: December 27, 2012
    Applicants: SONY CORPORATION, SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Yohei ENYA, Yusuke YOSHIZUMI, Takashi KYONO, Takamichi SUMITOMO, Masaki UENO, Katsunori YANASHIMA, Kunihiko TASAI, Hiroshi NAKAJIMA
  • Publication number: 20120299010
    Abstract: A III-nitride semiconductor device has a support base comprised of a III-nitride semiconductor and having a primary surface extending along a first reference plane perpendicular to a reference axis inclined at a predetermined angle with respect to a c-axis of the III-nitride semiconductor, and an epitaxial semiconductor region provided on the primary surface of the support base. The epitaxial semiconductor region includes GaN-based semiconductor layers. The reference axis is inclined at a first angle from the c-axis of the III-nitride semiconductor toward a first crystal axis, either the m-axis or a-axis. The reference axis is inclined at a second angle from the c-axis of the III-nitride semiconductor toward a second crystal axis, the other of the m-axis and a-axis. Morphology of an outermost surface of the epitaxial semiconductor region includes a plurality of pits. A pit density of the pits is not more than 5×104 cm?2.
    Type: Application
    Filed: May 31, 2012
    Publication date: November 29, 2012
    Applicant: Sumitomo Electric Industries, Ltd.
    Inventors: Yohei ENYA, Yusuke Yoshizumi, Takashi Kyono, Takamichi Sumitomo, Katsushi Akita, Masaki Ueno, Takao Nakamura
  • Patent number: 8306082
    Abstract: A group-III nitride semiconductor laser device comprises a laser structure including a support base and a semiconductor region, and an electrode provided on the semiconductor region of the laser structure. The support base comprises a hexagonal group-III nitride semiconductor and has a semipolar primary surface, and the semiconductor region is provided on the semipolar primary surface of the support base. The semiconductor region includes a first cladding layer of a first conductivity type gallium nitride-based semiconductor, a second cladding layer of a second conductivity type gallium nitride-based semiconductor, and an active layer. The first cladding layer, the second cladding layer, and the active layer are arranged along a normal axis to the semipolar primary surface. The active layer comprises a gallium nitride-based semiconductor layer.
    Type: Grant
    Filed: July 29, 2010
    Date of Patent: November 6, 2012
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Yusuke Yoshizumi, Yohei Enya, Takashi Kyono, Masahiro Adachi, Katsushi Akita, Masaki Ueno, Takamichi Sumitomo, Shinji Tokuyama, Koji Katayama, Takao Nakamura, Takatoshi Ikegami
  • Patent number: 8304269
    Abstract: A group III nitride semiconductor device having a gallium nitride based semiconductor film with an excellent surface morphology is provided. A group III nitride optical semiconductor device 11a includes a group III nitride semiconductor supporting base 13, a GaN based semiconductor region 15, an active layer active layer 17, and a GaN semiconductor region 19. The primary surface 13a of the group III nitride semiconductor supporting base 13 is not any polar plane, and forms a finite angle with a reference plane Sc that is orthogonal to a reference axis Cx extending in the direction of a c-axis of the group III nitride semiconductor. The GaN based semiconductor region 15 is grown on the semipolar primary surface 13a. A GaN based semiconductor layer 21 of the GaN based semiconductor region 15 is, for example, an n-type GaN based semiconductor, and the n-type GaN based semiconductor is doped with silicon.
    Type: Grant
    Filed: May 20, 2011
    Date of Patent: November 6, 2012
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Takashi Kyono, Yusuke Yoshizumi, Yohei Enya, Katsushi Akita, Masaki Ueno, Takamichi Sumitomo, Takao Nakamura
  • Patent number: 8304793
    Abstract: A III-nitride semiconductor optical device has a support base comprised of a III-nitride semiconductor, an n-type gallium nitride based semiconductor layer, a p-type gallium nitride based semiconductor layer, and an active layer. The support base has a primary surface at an angle with respect to a reference plane perpendicular to a reference axis extending in a c-axis direction of the III-nitride semiconductor. The n-type gallium nitride based semiconductor layer is provided over the primary surface of the support base. The p-type gallium nitride based semiconductor layer is doped with magnesium and is provided over the primary surface of the support base. The active layer is provided between the n-type gallium nitride based semiconductor layer and the p-type gallium nitride based semiconductor layer over the primary surface of the support base. The angle is in the range of not less than 40° and not more than 140°. The primary surface demonstrates either one of semipolar nature and nonpolar nature.
    Type: Grant
    Filed: July 14, 2010
    Date of Patent: November 6, 2012
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Yusuke Yoshizumi, Yohei Enya, Katsushi Akita, Masaki Ueno, Takashi Kyono, Takao Nakamura
  • Publication number: 20120273816
    Abstract: A semiconductor optical device includes: a group III nitride semiconductor substrate having a primary surface of a first orientation; a first group III nitride semiconductor laminate including a first active layer disposed on a first region of the primary surface; a group III nitride semiconductor thin film having a surface, which has a second orientation different from the first orientation, disposed on a second region, the second region being different from the first region; a junction layer provided between the second region and the group III nitride semiconductor thin film; and a second group III nitride semiconductor laminate including a second active layer and disposed on the surface of the group III nitride semiconductor thin film. The first and second active layers include first and second well layers containing In, respectively, and the emission wavelengths of the first and second well layers are different from each other.
    Type: Application
    Filed: March 29, 2012
    Publication date: November 1, 2012
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Takahisa YOSHIDA, Yohei ENYA, Takashi KYONO, Masaki UENO