Patents by Inventor Yukihiro Tsuji

Yukihiro Tsuji 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: 20230290858
    Abstract: A method for manufacturing a semiconductor device, includes forming source and drain electrodes on a semiconductor layer provided above a substrate; forming a first insulating film covering a surface of the semiconductor layer, between the source and drain electrodes, forming a second insulating film on the first insulating film, forming a mask on the second insulating film, the mask having an opening between the source and drain electrodes in a plan view viewed in a direction perpendicular to a substrate surface, forming a first gate opening in the first insulating film and forming a second gate opening in the second insulating film, by etching the first and second insulating films through the opening, and forming a gate electrode on the first and second insulating films, the gate electrode making a Schottky contact with the semiconductor layer through the first and second gate openings.
    Type: Application
    Filed: December 16, 2022
    Publication date: September 14, 2023
    Inventor: Yukihiro TSUJI
  • Publication number: 20230238447
    Abstract: A method of manufacturing a semiconductor device includes: forming an electron transit layer; forming an electron supply layer; forming a protective film; forming a zinc oxide film; forming a sacrifice layer; forming a first opening and a second opening in the sacrifice layer and the zinc oxide film; forming a third opening connecting to the first opening and a fourth opening connecting to the second opening; forming, by acid treatment using a weakly acidic solution, a first gap in a first portion exposed to the first opening of the zinc oxide film, and a second gap in a second portion exposed to the second opening of the zinc oxide film; forming, after the acid treatment, a source region on a bottom surface of the third opening and a drain region on a bottom surface of the fourth opening; and removing the zinc oxide film.
    Type: Application
    Filed: October 18, 2022
    Publication date: July 27, 2023
    Inventor: Yukihiro TSUJI
  • Publication number: 20230049363
    Abstract: A semiconductor device includes a substrate including a first main surface; a semiconductor layer provided on the first main surface of the substrate; an electrically insulating layer provided on the semiconductor layer; a source electrode and a drain electrode that are provided on the semiconductor layer; and a gate electrode provided on the electrically insulating layer. The semiconductor layer has an electron transport layer provided on the substrate and including a first upper surface, and has an electron supply layer provided on the electron transport layer. A first opening and a second opening are each formed in the electron supply layer and the electron transport layer. A third opening connected to the first opening and a fourth opening connected to the second opening are each formed in the electrically insulating layer.
    Type: Application
    Filed: July 20, 2022
    Publication date: February 16, 2023
    Inventor: Yukihiro TSUJI
  • Patent number: 11522343
    Abstract: A surface-emitting laser includes a substrate; semiconductor layers provided on the substrate, the semiconductor layers including a lower reflector layer, an active layer, and an upper reflector layer, the semiconductor layers forming a mesa; a first insulating film covering the mesa; and a second insulating film covering the first insulating film, wherein the mesa has a polygonal shape in a direction in which the substrate extends, and a vertex of the mesa in the direction in which the substrate extends has a chamfered portion.
    Type: Grant
    Filed: June 3, 2020
    Date of Patent: December 6, 2022
    Assignee: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventor: Yukihiro Tsuji
  • Patent number: 10998697
    Abstract: A method of manufacturing a surface emitting laser includes: preparing a substrate on which a lower reflector layer, an active layer and an upper reflector layer are formed in this order from the bottom, each of the lower reflector layer and the upper reflector layer including a semiconductor multilayer film; forming an insulating film on the upper reflector layer; cleaning the substrate using isopropyl alcohol after the forming; patterning a photoresist by applying the photoresist on the insulating film and exposing the photoresist, after the cleaning; and forming a high resistance region by implanting ions into portions of the lower reflector layer, the active layer and the upper reflector layer exposed from the photoresist, after the patterning; wherein the cleaning includes cleaning the substrate with a liquid of the isopropyl alcohol and drying the substrate in a vapor of the isopropyl alcohol.
    Type: Grant
    Filed: September 20, 2019
    Date of Patent: May 4, 2021
    Assignee: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventor: Yukihiro Tsuji
  • Patent number: 10916917
    Abstract: A method of manufacturing a surface emitting laser includes: forming a mesa by performing etching on a lower reflector layer, an active layer, and an upper reflector layer; forming a current narrowing layer by oxidizing a part of the upper reflector layer; exposing a substrate by performing etching on the lower reflector layer, the active layer, and the upper reflector layer, using a chlorine-containing gas; cleaning the substrate; performing heat treatment on the substrate; forming an insulating film covering a surface of the substrate; forming an electrode on the lower reflector layer and the upper reflector layer; and performing heat treatment on the substrate, wherein a temperature in the first heat treatment is lower than a temperature in the forming the current narrowing layer.
    Type: Grant
    Filed: September 20, 2019
    Date of Patent: February 9, 2021
    Assignee: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventor: Yukihiro Tsuji
  • Publication number: 20200412084
    Abstract: A vertical cavity surface-emitting laser includes a first insulating film provided on a semiconductor layer, the first insulating film having a recess, an identification mark provided in the recess of the first insulating film, the identification mark being formed of a metal layer, and a second insulating film provided over the semiconductor layer and covering the first insulating film and the metal layer. The metal layer has an upper surface located at a height equal to or lower than an upper surface of the first insulating film.
    Type: Application
    Filed: June 1, 2020
    Publication date: December 31, 2020
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventor: Yukihiro Tsuji
  • Publication number: 20200412094
    Abstract: A surface-emitting laser includes a substrate; semiconductor layers provided on the substrate, the semiconductor layers including a lower reflector layer, an active layer, and an upper reflector layer, the semiconductor layers forming a mesa; a first insulating film covering the mesa; and a second insulating film covering the first insulating film, wherein the mesa has a polygonal shape in a direction in which the substrate extends, and a vertex of the mesa in the direction in which the substrate extends has a chamfered portion.
    Type: Application
    Filed: June 3, 2020
    Publication date: December 31, 2020
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventor: Yukihiro TSUJI
  • Publication number: 20200412086
    Abstract: A vertical cavity surface-emitting laser includes a light emitting portion provided on a substrate, a first pad provided on the substrate, the first pad being electrically connected to the light emitting portion, and a second pad provided on the substrate, the second pad being electrically isolated from the light emitting portion and the first pad.
    Type: Application
    Filed: June 1, 2020
    Publication date: December 31, 2020
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventor: Yukihiro TSUJI
  • Publication number: 20200358251
    Abstract: A surface-emitting laser includes a light-emitting portion provided on a substrate; and two first electrodes and a second electrode provided over the substrate. At least one of the two first electrodes and the second electrode are electrically connected to the light-emitting portion. The at least one of the two first electrodes is one of a cathode electrode and an anode electrode. The second electrode is the other of the cathode electrode and the anode electrode. One of the two first electrodes and the second electrode are arranged in a first direction. The other of the two first electrodes and the second electrode are arranged in a second direction intersecting the first direction.
    Type: Application
    Filed: April 23, 2020
    Publication date: November 12, 2020
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventor: Yukihiro TSUJI
  • Publication number: 20200136351
    Abstract: A method of manufacturing a surface emitting laser includes: preparing a substrate on which a lower reflector layer, an active layer and an upper reflector layer are formed in this order from the bottom, each of the lower reflector layer and the upper reflector layer including a semiconductor multilayer film; forming an insulating film on the upper reflector layer; cleaning the substrate using isopropyl alcohol after the forming; patterning a photoresist by applying the photoresist on the insulating film and exposing the photoresist, after the cleaning; and forming a high resistance region by implanting ions into portions of the lower reflector layer, the active layer and the upper reflector layer exposed from the photoresist, after the patterning; wherein the cleaning includes cleaning the substrate with a liquid of the isopropyl alcohol and drying the substrate in a vapor of the isopropyl alcohol.
    Type: Application
    Filed: September 20, 2019
    Publication date: April 30, 2020
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventor: Yukihiro TSUJI
  • Publication number: 20200136352
    Abstract: A method of manufacturing a surface emitting laser includes: forming a mesa by performing etching on a lower reflector layer, an active layer, and an upper reflector layer; forming a current narrowing layer by oxidizing a part of the upper reflector layer; exposing a substrate by performing etching on the lower reflector layer, the active layer, and the upper reflector layer, using a chlorine-containing gas; cleaning the substrate; performing heat treatment on the substrate; forming an insulating film covering a surface of the substrate; forming an electrode on the lower reflector layer and the upper reflector layer; and performing heat treatment on the substrate, wherein a temperature in the first heat treatment is lower than a temperature in the forming the current narrowing layer.
    Type: Application
    Filed: September 20, 2019
    Publication date: April 30, 2020
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventor: Yukihiro TSUJI
  • Patent number: 10554010
    Abstract: A method of producing a semiconductor laser device includes the steps of preparing first and second substrate products each of which includes a substrate and a stacked semiconductor layer formed on the substrate, the first and second substrate products being different from each other; etching the first substrate product with a chlorine-based gas in a vacuum chamber by using a dry etching method; evacuating the vacuum chamber while monitoring the pressure of hydrogen chloride in the vacuum chamber so as to obtain a partial pressure of the hydrogen chloride within a predetermined range; after evacuating the vacuum chamber, introducing the second substrate product into the vacuum chamber while maintaining a vacuum state inside the vacuum chamber; and etching the second substrate product with a chlorine-based gas in the vacuum chamber by using the dry etching method.
    Type: Grant
    Filed: March 23, 2018
    Date of Patent: February 4, 2020
    Assignee: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventor: Yukihiro Tsuji
  • Patent number: 10476237
    Abstract: A quantum cascade laser includes: a substrate having a principal surface, a back surface, and a substrate end face, the substrate end face extending along a reference plane intersecting a second direction which intersects the first direction; a semiconductor laminate having a laminate end face extending along the reference plane; a first electrode disposed on the semiconductor laminate; a second electrode disposed on the substrate; a first insulating film disposed on the laminate end face and the first electrode; a metal film disposed on the first insulating film, the laminate end face, the substrate end face, and the second electrode; and a second insulating film disposed on the first electrode, the second insulating film having a part on the first electrode between the metal film and the semiconductor laminate. On the first electrode, the second insulating film has a thickness larger than that of the first insulating film.
    Type: Grant
    Filed: June 19, 2018
    Date of Patent: November 12, 2019
    Assignee: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Jun-ichi Hashimoto, Hiroyuki Yoshinaga, Yukihiro Tsuji
  • Patent number: 10234628
    Abstract: A method for producing a semiconductor device includes the steps of: providing a substrate product including a substrate and a first stacked semiconductor layer disposed on the substrate, the first stacked semiconductor layer including a plurality of semiconductor layers having different compositions that are alternately and periodically stacked with a predetermined period; forming a mask on the substrate product; and etching the first stacked semiconductor layer using the mask. The step of etching the first stacked semiconductor layer includes the steps of: optically monitoring an optical signal including a light component reflected from an etched surface of the substrate product for detecting an endpoint of etching; converting the optical signal to an electric signal to generate a monitoring signal; performing Fourier transform on the monitoring signal to generate a spectrum signal; and determining the endpoint detection of the etching by using the spectrum signal provided by the Fourier transform.
    Type: Grant
    Filed: September 25, 2017
    Date of Patent: March 19, 2019
    Assignee: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventor: Yukihiro Tsuji
  • Patent number: 10224697
    Abstract: An integrated quantum cascade laser includes: a laser structure including first to third regions arranged in a direction of a first axis, the laser structure including a substrate and a laminate including a core layer; first and second metal layers disposed on the third region; third and fourth metal layers disposed on the first region; first to fourth bump electrodes disposed on the first to fourth metal layers, respectively; first and second semiconductor mesas provided in the first region, each of the first and second semiconductor mesas including the core layer; and a distributed Bragg reflector provided in the second region, the distributed Bragg reflector having one or more semiconductor walls. The first and second metal layers are electrically connected to the first and second semiconductor mesas, respectively. The third and fourth metal layers are isolated from the first and second metal layers.
    Type: Grant
    Filed: July 25, 2017
    Date of Patent: March 5, 2019
    Assignee: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventor: Yukihiro Tsuji
  • Publication number: 20190067899
    Abstract: A method for fabricating a semiconductor optical device includes: preparing a product having a supporting base with a top face and a back face, a semiconductor product mounted on the top face, and an adhesive film with a film containing pressure sensitive material, the adhesive film being between the semiconductor product and the supporting base in the product, and the semiconductor product including a semiconductor laminate and a patterned resist layer on the semiconductor laminate; applying force to the product to produce an intermediate product from the product, the adhesive film bonding the semiconductor product and the top face of the supporting base to each other; disposing the intermediate product on a stage of an etching apparatus; and etching the semiconductor product in the intermediate product with the patterned resist layer in the etching apparatus while the semiconductor product being cooled through the stage.
    Type: Application
    Filed: August 21, 2018
    Publication date: February 28, 2019
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventor: Yukihiro TSUJI
  • Publication number: 20190064218
    Abstract: A probing device includes: a first probing needle including a first portion, a bent portion and a second portion, the first portion having a probing tip, and the bent portion connecting the first portion with the second portion; a second probing needle including a first portion, a bent portion and a second portion, the first portion having a probing tip, and the bent portion connecting the first portion with the second portion; a supporting member including an insulating base having a principal face and a back face, and the first probing needle and the second probing needle being supported by the insulating base on the back face; and a holder holding the first portions of the first and second probing needles, and the holder being apart from the probing tip of the first probing needle and the probing tip of the second probing needle.
    Type: Application
    Filed: August 9, 2018
    Publication date: February 28, 2019
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventor: Yukihiro TSUJI
  • Patent number: 10186832
    Abstract: A method for fabricating a surface emitting laser includes the steps of: preparing a processing apparatus with a first part and a second part, the processing apparatus including a first heater and a second heater that heat the first part and the second part, respectively; preparing a wafer product for forming a surface emitting laser, the wafer product including a semiconductor post including a III-V compound semiconductor layer containing aluminum as a constituent element, the III-V compound semiconductor layer being exposed at a side face of the semiconductor post; after disposing the wafer product in the second part, energizing the first heater and the second heater; supplying a first gas containing no oxidizing agent to the processing apparatus; and after stopping supplying the first gas, oxidizing the III-V compound semiconductor layer by supplying a second gas containing an oxidizing agent to the processing apparatus.
    Type: Grant
    Filed: March 15, 2017
    Date of Patent: January 22, 2019
    Assignee: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventor: Yukihiro Tsuji
  • Patent number: 10170890
    Abstract: A surface-emitting semiconductor laser has a semiconductor structure that includes a first side, a second side opposite to the first side, and a side surface that extends from the second side to the first side; a first electrode provided on the first side of the semiconductor structure; and a second electrode provided on the first side of the semiconductor structure. The semiconductor structure also includes a substrate, a first stacked semiconductor layer disposed on the substrate, an active layer disposed on the first stacked semiconductor layer, and a second stacked semiconductor layer disposed on the active layer. The first stacked semiconductor layer includes a first distributed Bragg reflector, and the second stacked semiconductor layer includes a second distributed Bragg reflector. The semiconductor structure side surface has at least an upper surface that is free of chipping.
    Type: Grant
    Filed: February 27, 2018
    Date of Patent: January 1, 2019
    Assignee: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventor: Yukihiro Tsuji