Patents by Inventor Sadayoshi Matsui

Sadayoshi Matsui 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: 6206969
    Abstract: A semiconductor fabrication apparatus for evaporating a material in a growth chamber by a molecular beam epitaxy technique to fabricate a semiconductor is provided. The apparatus includes: an ultra-high vacuum chamber including a liquid nitrogen cold trap therein, the ultra-high vacuum chamber being connected to the growth chamber via a valve; a first evacuation system including an ultra-high vacuum evacuation system, the first evacuation system being connected to the ultra-high vacuum chamber; and a second evacuation system including an evacuation system capable of conducting an evacuation operation even in a low vacuum condition, the second evacuation system being connected to the liquid nitrogen cold trap. The first evacuation system and the second evacuation system independently conduct the respective evacuation operations.
    Type: Grant
    Filed: May 9, 1997
    Date of Patent: March 27, 2001
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Kosei Takahashi, Sadayoshi Matsui
  • Patent number: 5789773
    Abstract: In an AlGaInP type semiconductor light-emitting device, an n-type AlGaInP cladding layer and a p-type AlGaInP cladding layer are deposited so as to interpose an active layer made of GaInP or AlGaInP therebetween. Light guiding layers are provided between the active layer and the n-type cladding layer, and/or, between the active layer and the p-type cladding layer, respectively. The p-type cladding layer is doped with Be serving as a p-type dopant. The active layer, the p-type cladding layer and the light guiding layers are doped with Si which may serve as an n-type dopant.
    Type: Grant
    Filed: October 1, 1996
    Date of Patent: August 4, 1998
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Tadashi Takeoka, Sadayoshi Matsui
  • Patent number: 5491106
    Abstract: A method for growing a compound semiconductor layer of Al.sub.x Ga.sub.1-x As (0.ltoreq.x.ltoreq.1) on a compound semiconductor substrate uses a molecular beam epitaxial apparatus, the method including the steps of providing the substrate having a GaAs layer on an upper surface thereof, thermally etching the GaAs layer by heating the substrate at a temperature and irradiating the GaAs layer with a gallium molecular beam and an arsenic molecular beam to expose the upper surface of the substrate, and growing the Al.sub.x Ga.sub.1-x As (0.ltoreq.x.ltoreq.1) layer on the upper surface of the substrate.
    Type: Grant
    Filed: July 23, 1993
    Date of Patent: February 13, 1996
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Akinori Seki, Hiroyuki Hosoba, Toshio Hata, Masafumi Kondo, Takahiro Suyama, Sadayoshi Matsui
  • Patent number: 5450237
    Abstract: A hyper-resolution optical device which can focus a beam of light to a diameter less than the diffraction limit. The optical device has an optical system disposed on a transmissive substrate. One component in the optical system is a hyper-resolution optical component which passes or reflects light and which has a central portion which does not pass or reflect light, respectively. The hyper-resolution optical component can be integrated with the transmissive substrate. Such optical devices are particularly suitable for optical pick-up devices, laser printers, sensors.
    Type: Grant
    Filed: September 2, 1994
    Date of Patent: September 12, 1995
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Toshihiko Yoshida, Osamu Yamamoto, Saburo Yamamoto, Shohichi Kato, Masumi Nakamichi, Toshimasa Hamada, Sadayoshi Matsui
  • Patent number: 5360762
    Abstract: On a GaAs substrate (Al.sub.Y Ga.sub.1-Y).sub.0.5 In.sub.0.5 P crystal layers (0.ltoreq.Y.ltoreq.1) is formed to be lattice-matched with the substrate. By radiating As molecular beams on the surface of the crystal layers while heating the layered substrate to a temperature at which In in the crystal layers evaporates, the portion near the surface of the crystal layers is changed into an Al.sub.Y Ga.sub.1-Y As crystal layer (0.ltoreq.Y.ltoreq.1) of a thickness of several molecules, on which layer an Al.sub.X Ga.sub.1-X As crystal layer (0.ltoreq.X.ltoreq.1) is formed. Since the surface of the Al.sub.Y Ga.sub.1-Y As crystal layer has been purl fled, the formed Al.sub.X Ga.sub.1-X As crystal layer has a high crystallinity, allowing production of a light emitting diode, a semiconductor laser device and the like with high efficiency.
    Type: Grant
    Filed: June 21, 1993
    Date of Patent: November 1, 1994
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Kosei Takahashi, Masahiro Hosoda, Atsuo Tsunoda, Takahiro Suyama, Sadayoshi Matsui
  • Patent number: 5271028
    Abstract: A semiconductor laser device which can effectively confine electrons and positive holes is disclosed. The semiconductor laser device includes a semiconductor substrate of a first conductivity type, a current blocking layer of a second conductivity type, a first semiconductor layer of the first conductivity type made of a III-V group compound semiconductor, an active layer made of a III-V group compound semiconductor, and a second semiconductor layer. The semiconductor substrate has a ridge-type mesa having (n11)A planes. The current blocking layer is formed on the semiconductor substrate other than the top face of the mesa. The first semiconductor layer is formed on the entire surface of the current blocking layer and on the top face of the mesa. The active layer is formed on the first semiconductor layer. The second semiconductor layer is formed on the active layer.
    Type: Grant
    Filed: July 22, 1992
    Date of Patent: December 14, 1993
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Masafumi Kondo, Takahiro Suyama, Shinji Kaneiwa, Toshio Hata, Hiroyuki Hosoba, Sadayoshi Matsui
  • Patent number: 5255279
    Abstract: On a GaAs substrate (Al.sub.Y Ga.sub.1-Y).sub.0.5 In.sub.0.5 P crystal layers (0.ltoreq.Y.ltoreq.1) is formed to be lattice-matched with the substrate. By radiating As molecular beams on the surface of the crystal layers while heating the layered substrate to a temperature at which In in the crystal layers evaporates, the portion near the surface of the crystal layers is changed into an Al.sub.Y Ga.sub.1-Y As crystal layer (0.ltoreq.Y.ltoreq.1) of a thickness of several molecules, on which layer an Al.sub.X Ga.sub.1-X As crystal layer (0.ltoreq.X.ltoreq.1) is formed. Since the surface of the Al.sub.Y Ga.sub.1-Y As crystal layer has been purified, the formed Al.sub.X Ga.sub.1-X As crystal layer has a high crystallinity, allowing production of a light emitting diode, a semiconductor laser device and the like with high efficiency.
    Type: Grant
    Filed: May 9, 1991
    Date of Patent: October 19, 1993
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Kosei Takahashi, Masahiro Hosoda, Atsuo Tsunoda, Takahiro Suyama, Sadayoshi Matsui
  • Patent number: 5206185
    Abstract: A semiconductor laser device is disclosed which comprises a semiconductor substrate having a ridge portion, the width of the ridge portion being smaller in the vicinity of the facets than in the inside of the device; a current blocking layer formed on the substrate including the ridge portion; at least one striped groove formed on the center of the ridge portion through the current blocking layer; and a multi-layered structure disposed on the current blocking layer, the multi-layered structure successively having a first current blocking layer, an active layer for laser oscillation, and a second current blocking layer; wherein at least two side grooves are symmetrically formed on both sides of the center region of the ridge portion with the same width as that of the regions thereof near the facets. Also, disclosed is a method for producing the semiconductor laser device.
    Type: Grant
    Filed: May 30, 1991
    Date of Patent: April 27, 1993
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Hiroyuki Hosoba, Mitsuhiro Matsumoto, Sadayoshi Matsui, Taiji Morimoto
  • Patent number: 5111470
    Abstract: A semiconductor laser device is provided which includes a semiconductor substrate and a multi-layered structure disposed on the substrate, the multi-layered structure containing an Al.sub.x Ga.sub.1-x As (0<x<1) first cladding layer formed on the substrate, an Al.sub.y Ga.sub.1-y As (0<y<1, x>y) active layer for laser oscillation formed on the first cladding layer, an Al.sub.x Ga.sub.1-x As (0<x<1) second cladding layer formed on the active layer, and an Al.sub.z Ga.sub.1-z As (0<z<1) current blocking layer formed above the second cladding layer, the current blocking layer having a striped groove as a current injection path. The method includes the steps of: forming a multi-layered structure on a semiconductor substrate, the multi-layered structure containing in order, an Al.sub.x Ga.sub.1-x As (0<x<1) first cladding layer, an Al.sub.y Ga.sub.
    Type: Grant
    Filed: April 12, 1991
    Date of Patent: May 5, 1992
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Hiroyuki Hosoba, Akinori Seki, Toshio Hata, Masafumi Kondou, Takahiro Suyama, Sadayoshi Matsui
  • Patent number: 5054031
    Abstract: A semiconductor laser device is disclosed which comprises a semiconductor substrate having a ridge portion, the width of the ridge portion being smaller in the vicinity of the facets than in the inside of the device; a current blocking layer formed on the substrate including the ridge portion; at least one striped groove formed on the center of the ridge portion through the current blocking layer; and a multi-layered structure disposed on the current blocking layer, the multi-layered structure successively having a first current blocking layer, an active layer for laser oscillation, and a second current blocking layer; wherein at least two side grooves are symmetrically formed on both sides of the center region of the ridge portion with the same width as that of the regions thereof near the facets. Also, disclosed is a method for producing the semiconductor laser device.
    Type: Grant
    Filed: December 22, 1989
    Date of Patent: October 1, 1991
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Hiroyuki Hosoba, Mitsuhiro Matsumoto, Sadayoshi Matsui, Taiji Morimoto
  • Patent number: 5042044
    Abstract: A semiconductor laser device and a method for the production of the semiconductor laser device are provided, which semiconductor laser device includes a striped channel formed in a semiconductor substrate through a current blocking layer on the substrate and at least two dummy grooves formed in the current blocking layer on each side of the striped channel. Also provided are a semiconductor wafer prepared for the purpose of producing optical devices with an optical waveguide, and a method for the production of the semiconductor wafer. The semiconductor wafer includes a semiconductor substrate, the surface of which has an orientation inclined from the [100] direction to one of the [011] and [011] directions of an angle .theta. satisfying the relationship 0.1.degree.<.vertline..theta..vertline.<4.degree.
    Type: Grant
    Filed: April 27, 1990
    Date of Patent: August 20, 1991
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Masaki Kondo, Kazuaki Sasaki, Taiji Morimoto, Mitsuhiro Matsumoto, Hiroyuki Hosoba, Sadayoshi Matsui, Saburo Yamamoto, Takahiro Suyama, Masafumi Kondo
  • Patent number: 4997747
    Abstract: A method for the formation of a diffraction grating on a substrate using a holographic technique and an etching technique, wherein the periodicity of the pattern of the diffraction grating can be changed at will by a change of the light-path length of one of the two light fluxes from a holographic exposing system.
    Type: Grant
    Filed: October 5, 1988
    Date of Patent: March 5, 1991
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Toshihiko Yoshida, Haruhisa Takiguchi, Shinji Kaneiwa, Sadayoshi Matsui
  • Patent number: 4939737
    Abstract: A scanning apparatus with a refracting function comprising a laser beam oscillating area, one or more refracting areas with a waveguide having different refractive indexes, wherein an electric field is applied to the waveguide of the refracting area, by which the changes in the refractive index of the waveguide of the refracting area are attained so that laser beams from the laser beam oscillating area undergo refraction while they pass through the waveguide of the refracting area.
    Type: Grant
    Filed: February 16, 1988
    Date of Patent: July 3, 1990
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Sadayoshi Matsui, mototaka Taneya, Mitsuhiro Matsumoto
  • Patent number: 4914669
    Abstract: A semiconductor laser array apparatus comprising a single substrate and a plurality of semiconductor laser devices that are disposed with a given pitch on the substrate, some of the semiconductor laser devices constituting laser devices of a laser oscillation-operating area of the semiconductor laser array apparatus and the other semiconductor laser devices constituting laser devices of the non-laser oscillation-operating areas that are positioned outside of the laser oscillation-operating area, wherein the oscillation threshold current level of at least one of the semiconductor laser devices of each of the non-laser oscillation-operating areas that is the closest to the laser oscillation-operating area is higher than those of the semiconductor laser devices of the laser oscillation-operating area.
    Type: Grant
    Filed: July 22, 1988
    Date of Patent: April 3, 1990
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Sadayoshi Matsui, Mototaka Taneya, Mitsuhiro Matsumoto, Hiroyuki Hosoba
  • Patent number: 4908831
    Abstract: A buried type semiconductor laser device comprising a multi-layered epitaxial growth crystal including a striped laser-oscillation operating area on a semiconductor substrate, wherein said laser-oscillation operating area contains a buffer layer having the same polarity as said substrate, an active layer and a cladding layer having a polarity different from that of said substrate, said laser-oscillation operation area being sandwiched between one part of the burying layer and another part of the burying layer, which are disposed on said substrate and which have a polarity different from that of said substrate, through said substrate or a diffusion region having an impurity with the same polarity as said substrate so as to electrically isolate said burying layer from said cladding layer, thereby maintaining ineffective current flowing from said cladding layer to said burying layer at a low level even when current injected into said device is increased.
    Type: Grant
    Filed: February 22, 1989
    Date of Patent: March 13, 1990
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Toshihiko Yoshida, Haruhisa Takiguchi, Shinji Kaneiwa, Hiroaki Kudo, Sadayoshi Matsui
  • Patent number: 4908830
    Abstract: A buried type semiconductor laser device comprising a multi-layered epitaxial growth crystal including a striped laser-oscillation operating area on a semiconductor substrate, wherein said laser-oscillation operating area contains a buffer layer having the same polarity as said substrate, an active layer and a cladding layer having a polarity different from that of said substrate, said laser-oscillation operating area being sandwiched between one part of the burying layer and another part of the burying layer, which are disposed on said substrate and which have a polarity different from that of said substrate, through said substrate or a diffusion region having an impurity with the same polarity as said substrate so as to electrically isolate said burying layer from said cladding layer, thereby maintaining ineffective current flowing from said cladding layer to said burying layer at a low level even when current injected into said device is increased.
    Type: Grant
    Filed: February 22, 1989
    Date of Patent: March 13, 1990
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Toshihiko Yoshida, Haruhisa Takiguchi, Shinji Kaneiwa, Hiroaki Kudo, Sadayoshi Matsui
  • Patent number: 4903274
    Abstract: A semiconductor laser array device comprising a substrate with a plurality of grooves and an active layer disposed over the substrate, resulting in optical waveguides within the active layer corresponding to the grooves, wherein the grooves are disposed over the entire area of the substrate and a means for preventing the injection of current into some of the grooves that are positioned outside of the central area of the substrate is disposed whereby the other grooves positioned in the central area of the substrate consitute a laser array portion of the semiconductor laser array device.
    Type: Grant
    Filed: May 18, 1988
    Date of Patent: February 20, 1990
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Mototaka Taneya, Mitsuhiro Matsumoto, Sadayoshi Matsui, Hiroyuki Hosoba
  • Patent number: 4901328
    Abstract: A V-channeled substrate inner strip (VSIS) semiconductor laser includes a p-Ga.sub.1-31 y Al.sub.y As active layer sandwiched between a P-Ga.sub.1-x Al.sub.x As first cladding layer and an n-Ga.sub.1-x Al.sub.x As second cladding layer. The AlAs mole fraction x of the first and second cladding layers is selected between about 0.45 and 0.52 in order to minimize the mode competition noise at an operating temperature. In a preferred form, the cavity length is longer than 300 .mu.m so as to minimize the occurrence of the mode competition noise at the operating temperature. Furthermore, the reflectivity R.sub.1 of the front facet and the reflectivity R.sub.2 of the rear facet are selected to satisfy the condition 0.1.ltoreq.ln(1/R.sub.1 .multidot.R.sub.2).ltoreq.1.
    Type: Grant
    Filed: July 17, 1989
    Date of Patent: February 13, 1990
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Sadayoshi Matsui, Haruhisa Takiguchi, Shinji Kaneiwa, Mototaka Taneya
  • Patent number: 4890293
    Abstract: A semiconductor laser device comprising a first layer that is of a first conductivity type; a second layer that is disposed on the first layer, the second layer having a forbidden bandgap smaller than that of the first layer and having a refraction index larger than that of the first layer; a third layer that is of a second conductivity type; the third layer being disposed over the second layer, having a forbidden bandgap larger than that of the second layer, and having a refraction index smaller than that of the second layer; a fourth layer that functions as a quantum wall, the fourth layer being disposed between the second and third layers and the thickness of the fourth layer being the de Broglie's wavelength or less; and at least one striped mesa, the lower portion of which is constituted by the third layer, wherein the fourth layer has a forbidden bandgap that is larger than that of the energy of photons generated by the second layer, and moreover the fourth layer has the etching characteristics that are
    Type: Grant
    Filed: October 7, 1988
    Date of Patent: December 26, 1989
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Mototaka Taneya, Kosei Takahashi, Toshiro Hayakawa, Sadayoshi Matsui, Mitsuhiro Matsumoto, Hiroyuki Hosoba
  • Patent number: 4878223
    Abstract: A semiconductor laser array device comprising a substrate with a plurality of grooves and an active layer disposed over the substrate, resulting in optical waveguides within the active layer corresponding to the grooves, wherein the grooves are disposed over the entire area of the substrate and a means for preventing the injection of current into some of the grooves that are positioned outside of the central area of the substrate is disposed whereby the other grooves positioned in the central area of the substrate constitute a laser array portion of the semiconductor laser array device.
    Type: Grant
    Filed: July 26, 1988
    Date of Patent: October 31, 1989
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Taiji Morimoto, Hiroyuki Hosoba, Mitsuhiro Matsumoto, Mototaka Taneya, Sadayoshi Matsui