Patents by Inventor Gregor Keller

Gregor Keller 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: 11955334
    Abstract: A vapor phase epitaxy method of growing a III-V layer with a doping profile that changes from a p-doping to an n-doping on a surface of a substrate or a preceding layer from the vapor phase from an epitaxial gas flow, at least one first precursor for an element of main group III, and at least one second precursor for an element of main group V. When a first growth height is reached, a first initial doping level is set by means of a ratio of a first mass flow of the first precursor to a second mass flow of the second precursor in the epitaxial gas flow, and subsequently, by stepwise or continuously changing the ratio of the first mass flow to the second mass flow and by stepwise or continuously increasing a mass flow of a third precursor for an n-type dopant in the epitaxial gas flow.
    Type: Grant
    Filed: December 21, 2020
    Date of Patent: April 9, 2024
    Assignee: AZUR SPACE Solar Power GmbH
    Inventors: Gregor Keller, Clemens Waechter, Thorsten Wierzkowski
  • Patent number: 11859310
    Abstract: A vapor phase epitaxy method of growing a III-V layer with a doping that changes from a first conductivity type to a second conductivity type on a surface of a substrate or a preceding layer in a reaction chamber from the vapor phase from an epitaxial gas flow comprising a carrier gas, at least one first precursor for an element from main group III, and at least one second precursor for an element from main group V, wherein when a first growth height is reached, a first initial doping level of the first conductivity type is set by means of a ratio of a first mass flow of the first precursor to a second mass flow of the second precursor in the epitaxial gas flow, the first initial doping level is then reduced to a second initial doping level of the first or low second conductivity type.
    Type: Grant
    Filed: December 21, 2020
    Date of Patent: January 2, 2024
    Assignee: Azur Space Solar Power GmbH
    Inventors: Clemens Waechter, Gregor Keller, Daniel Fuhrmann
  • Patent number: 11728453
    Abstract: A stacked monolithic multijunction solar cell, which includes a first subcell having a p-n junction with an emitter layer and a base layer, the thickness of the emitter layer being less than the thickness of the base layer at least by a factor of ten, and the first subcell comprising a substrate having a semiconductor material from the groups III and V or a substrate from the group IV, and which further includes a second subcell arranged on the first subcell and a third subcell arranged on the second subcell, the two subcells each including an emitter layer and a base layer, and a tunnel diode and a back side field layer each being formed between the subcells, the thickness of the emitter layer being greater than the thickness of the base layer in each case between the second subcell and in the third subcell.
    Type: Grant
    Filed: July 12, 2021
    Date of Patent: August 15, 2023
    Assignee: AZUR SPACE Solar Power GmbH
    Inventors: Daniel Fuhrmann, Rosalinda Van Leest, Gregor Keller, Matthias Meusel
  • Patent number: 11715766
    Abstract: A stacked high barrier III-V power semiconductor diode having an at least regionally formed first metallic terminal contact layer and a heavily doped semiconductor contact region of a first conductivity type with a first lattice constant, a drift layer of a second conductivity type, a heavily doped metamorphic buffer layer sequence of the second conductivity type is formed. The metamorphic buffer layer sequence has an upper side with the first lattice constant and a lower side with a second lattice constant. The first lattice constant is greater than the second lattice constant. The upper side of the metamorphic buffer layer sequence is arranged in the direction of the drift layer. A second metallic terminal contact layer is arranged below the lower side of the metamorphic buffer layer sequence. The second metallic terminal contact layer is integrally bonded with a semiconductor contact layer.
    Type: Grant
    Filed: December 22, 2021
    Date of Patent: August 1, 2023
    Assignee: AZUR SPACE Solar Power GmbH
    Inventors: Daniel Fuhrmann, Gregor Keller, Clemens Waechter
  • Patent number: 11699722
    Abstract: A stacked, high-blocking III-V semiconductor power diode having a first metallic terminal contact layer, formed at least in regions, and a highly doped semiconductor contact region of a first conductivity type and a first lattice constant. A drift layer of a second conductivity type and having a first lattice constant is furthermore provided. A semiconductor contact layer of a second conductivity, which includes an upper side and an underside, and a second metallic terminal contact layer are formed, and the second metallic terminal contact layer being integrally connected to the underside of the semiconductor contact layer, and the semiconductor contact layer having a second lattice constant at least on the underside, and the second lattice constant being the lattice constant of InP, and the drift layer and the highly doped semiconductor contact region each comprising an InGaAs compound or being made up of InGaAs.
    Type: Grant
    Filed: January 19, 2022
    Date of Patent: July 11, 2023
    Assignees: AZUR SPACE, 3-5 Power Electronics GmbH
    Inventors: Daniel Fuhrmann, Gregor Keller, Clemens Waechter, Volker Dudek
  • Patent number: 11598022
    Abstract: A vapor phase epitaxy method of growing a III-V layer with a doping that changes from a first conductivity type to a second conductivity type on a surface of a substrate or a preceding layer in a reaction chamber from the vapor phase from an epitaxial gas flow comprising a carrier gas, at least one first precursor for an element from main group III, and at least one second precursor for an element from main group V, wherein when a first growth height is reached, a first initial doping level of the first conductivity type is set by means of a ratio of a first mass flow of the first precursor to a second mass flow of the second precursor, then the first initial doping level is reduced to a second initial doping level of the first or low second conductivity type.
    Type: Grant
    Filed: December 21, 2020
    Date of Patent: March 7, 2023
    Assignee: AZUR SPACE Solar Power GmbH
    Inventors: Clemens Waechter, Gregor Keller, Daniel Fuhrmann
  • Patent number: 11557665
    Abstract: A vertical high-blocking III-V bipolar transistor, which includes an emitter, a base and a collector. The emitter has a highly doped emitter semiconductor contact region of a first conductivity type and a first lattice constant. The base has a low-doped base semiconductor region of a second conductivity type and the first lattice constant. The collector has a layered low-doped collector semiconductor region of the first conductivity type with a layer thickness greater than 10 ?m and the first lattice constant. The collector has a layered highly doped collector semiconductor contact region of the first conductivity type. A first metallic connecting contact layer is formed in regions being integrally connected to the emitter. A second metallic connecting contact layer is formed in regions being integrally connected to the base. A third metallic connecting contact region is formed at least in regions being arranged beneath the collector.
    Type: Grant
    Filed: July 6, 2021
    Date of Patent: January 17, 2023
    Assignee: AZUR SPACE Solar Power GmbH
    Inventors: Gregor Keller, Clemens Waechter, Daniel Fuhrmann
  • Publication number: 20220140088
    Abstract: A stacked, high-blocking III-V semiconductor power diode having a first metallic terminal contact layer, formed at least in regions, and a highly doped semiconductor contact region of a first conductivity type and a first lattice constant. A drift layer of a second conductivity type and having a first lattice constant is furthermore provided. A semiconductor contact layer of a second conductivity, which includes an upper side and an underside, and a second metallic terminal contact layer are formed, and the second metallic terminal contact layer being integrally connected to the underside of the semiconductor contact layer, and the semiconductor contact layer having a second lattice constant at least on the underside, and the second lattice constant being the lattice constant of InP, and the drift layer and the highly doped semiconductor contact region each comprising an InGaAs compound or being made up of InGaAs.
    Type: Application
    Filed: January 19, 2022
    Publication date: May 5, 2022
    Applicants: AZUR SPACE Solar Power GmbH, 3-5 Power Electronics GmbH
    Inventors: Daniel FUHRMANN, Gregor KELLER, Clemens WAECHTER, Volker DUDEK
  • Publication number: 20220115501
    Abstract: A stacked high barrier III-V power semiconductor diode having an at least regionally formed first metallic terminal contact layer and a heavily doped semiconductor contact region of a first conductivity type with a first lattice constant, a drift layer of a second conductivity type, a heavily doped metamorphic buffer layer sequence of the second conductivity type is formed. The metamorphic buffer layer sequence has an upper side with the first lattice constant and a lower side with a second lattice constant. The first lattice constant is greater than the second lattice constant. The upper side of the metamorphic buffer layer sequence is arranged in the direction of the drift layer. A second metallic terminal contact layer is arranged below the lower side of the metamorphic buffer layer sequence. The second metallic terminal contact layer is integrally bonded with a semiconductor contact layer.
    Type: Application
    Filed: December 22, 2021
    Publication date: April 14, 2022
    Applicant: AZUR SPACE Solar Power GmbH
    Inventors: Daniel FUHRMANN, Gregor KELLER, Clemens WAECHTER
  • Patent number: 11280025
    Abstract: A vapor phase epitaxy method including: providing a III-V substrate of a first conductivity type, introducing the III-V substrate into a reaction chamber of a vapor phase epitaxy system at a loading temperature, heating the III-V substrate from the loading temperature to an epitaxy temperature while introducing an initial gas flow, depositing a III-V layer with a dopant concentration of a dopant of the first conductivity type on a surface of the III-V substrate from the vapor phase from an epitaxial gas flow, fed into the reaction chamber and comprising the carrier gas, the first precursor, and at least one second precursor for an element of main group III, wherein during the heating from the loading temperature to the epitaxy temperature, a third precursor for a dopant of the first conductivity type is added to the initial gas flow.
    Type: Grant
    Filed: December 21, 2020
    Date of Patent: March 22, 2022
    Assignee: AZUR SPACE Solar Power GmbH
    Inventors: Clemens Waechter, Gregor Keller
  • Patent number: 11257909
    Abstract: A stacked, high-blocking III-V semiconductor power diode having a first metallic terminal contact layer, formed at least in regions, and a highly doped semiconductor contact region of a first conductivity type and a first lattice constant. A drift layer of a second conductivity type and having a first lattice constant is furthermore provided. A semiconductor contact layer of a second conductivity, which includes an upper side and an underside, and a second metallic terminal contact layer are formed, and the second metallic terminal contact layer being integrally connected to the underside of the semiconductor contact layer, and the semiconductor contact layer having a second lattice constant at least on the underside, and the second lattice constant being the lattice constant of InP, and the drift layer and the highly doped semiconductor contact region each comprising an InGaAs compound or being made up of InGaAs.
    Type: Grant
    Filed: April 30, 2020
    Date of Patent: February 22, 2022
    Assignees: AZUR SPACE Solar Power GmbH, 3-5 Power Electronics GmbH
    Inventors: Daniel Fuhrmann, Gregor Keller, Clemens Waechter, Volker Dudek
  • Patent number: 11245012
    Abstract: A stacked high barrier III-V power semiconductor diode having an at least regionally formed first metallic terminal contact layer and a heavily doped semiconductor contact region of a first conductivity type with a first lattice constant, a drift layer of a second conductivity type, a heavily doped metamorphic buffer layer sequence of the second conductivity type is formed. The metamorphic buffer layer sequence has an upper side with the first lattice constant and a lower side with a second lattice constant. The first lattice constant is greater than the second lattice constant. The upper side of the metamorphic buffer layer sequence is arranged in the direction of the drift layer. A second metallic terminal contact layer is arranged below the lower side of the metamorphic buffer layer sequence. The second metallic terminal contact layer is integrally bonded with a semiconductor contact layer.
    Type: Grant
    Filed: April 30, 2020
    Date of Patent: February 8, 2022
    Assignee: AZUR SPACE Solar Power GmbH
    Inventors: Daniel Fuhrmann, Gregor Keller, Clemens Waechter
  • Publication number: 20220013676
    Abstract: A stacked monolithic multijunction solar cell, which includes a first subcell having a p-n junction with an emitter layer and a base layer, the thickness of the emitter layer being less than the thickness of the base layer at least by a factor of ten, and the first subcell comprising a substrate having a semiconductor material from the groups III and V or a substrate from the group IV, and which further includes a second subcell arranged on the first subcell and a third subcell arranged on the second subcell, the two subcells each including an emitter layer and a base layer, and a tunnel diode and a back side field layer each being formed between the subcells, the thickness of the emitter layer being greater than the thickness of the base layer in each case between the second subcell and in the third subcell.
    Type: Application
    Filed: July 12, 2021
    Publication date: January 13, 2022
    Applicant: AZUR SPACE Solar Power GmbH
    Inventors: Daniel FUHRMANN, Rosalinda VAN LEEST, Gregor KELLER, Matthias MEUSEL
  • Publication number: 20220005942
    Abstract: A vertical high-blocking III-V bipolar transistor, which includes an emitter, a base and a collector. The emitter has a highly doped emitter semiconductor contact region of a first conductivity type and a first lattice constant. The base has a low-doped base semiconductor region of a second conductivity type and the first lattice constant. The collector has a layered low-doped collector semiconductor region of the first conductivity type with a layer thickness greater than 10 ?m and the first lattice constant. The collector has a layered highly doped collector semiconductor contact region of the first conductivity type. A first metallic connecting contact layer is formed in regions being integrally connected to the emitter. A second metallic connecting contact layer is formed in regions being integrally connected to the base. A third metallic connecting contact region is formed at least in regions being arranged beneath the collector.
    Type: Application
    Filed: July 6, 2021
    Publication date: January 6, 2022
    Applicant: AZUR SPACE Solar Power GmbH
    Inventors: Gregor KELLER, Clemens WAECHTER, Daniel FUHRMANN
  • Publication number: 20210193464
    Abstract: A vapor phase epitaxy method of growing a III-V layer with a doping profile that changes from a p-doping to an n-doping on a surface of a substrate or a preceding layer from the vapor phase from an epitaxial gas flow, at least one first precursor for an element of main group III, and at least one second precursor for an element of main group V. When a first growth height is reached, a first initial doping level is set by means of a ratio of a first mass flow of the first precursor to a second mass flow of the second precursor in the epitaxial gas flow, and subsequently, by stepwise or continuously changing the ratio of the first mass flow to the second mass flow and by stepwise or continuously increasing a mass flow of a third precursor for an n-type dopant in the epitaxial gas flow.
    Type: Application
    Filed: December 21, 2020
    Publication date: June 24, 2021
    Applicant: AZUR SPACE SOLAR POWER GMBH
    Inventors: Gregor KELLER, Clemens WAECHTER, Thorsten Wierzkowski
  • Publication number: 20210189595
    Abstract: A vapor phase epitaxy method of growing a III-V layer with a doping that changes from a first conductivity type to a second conductivity type on a surface of a substrate or a preceding layer in a reaction chamber from the vapor phase from an epitaxial gas flow comprising a carrier gas, at least one first precursor for an element from main group III, and at least one second precursor for an element from main group V, wherein when a first growth height is reached, a first initial doping level of the first conductivity type is set by means of a ratio of a first mass flow of the first precursor to a second mass flow of the second precursor, then the first initial doping level is reduced to a second initial doping level of the first or low second conductivity type.
    Type: Application
    Filed: December 21, 2020
    Publication date: June 24, 2021
    Applicant: AZUR SPACE SOLAR POWER GMBH
    Inventors: Clemens WAECHTER, Gregor KELLER, Daniel FUHRMANN
  • Publication number: 20210193463
    Abstract: A vapor phase epitaxy method of growing a III-V layer with a doping profile that changes from n-doping to p-doping on a surface of a substrate or a preceding layer in a reaction chamber from the vapor phase of an epitaxial gas flow, comprising at least one carrier gas, a first precursor for a first element from main group III and at least one second precursor for a first element from main group V, and fed into the reaction chamber, wherein, when a first growth level is reached, an initial n-doping level is set by means of a ratio, leading to a p-doping, of a first mass flow of the first precursor to a second mass flow of the second precursor in the epitaxial gas flow and with the addition of a third mass flow of a third precursor for an n-type dopant to the epitaxial gas flow, subsequently.
    Type: Application
    Filed: December 21, 2020
    Publication date: June 24, 2021
    Applicant: AZUR SPACE SOLAR POWER GMBH
    Inventors: Clemens WAECHTER, Gregor KELLER, Thorsten WIERZKOWSKI, Daniel FUHRMANN
  • Publication number: 20210189592
    Abstract: A vapor phase epitaxy method including: providing a III-V substrate of a first conductivity type, introducing the III-V substrate into a reaction chamber of a vapor phase epitaxy system at a loading temperature, heating the III-V substrate from the loading temperature to an epitaxy temperature while introducing an initial gas flow, depositing a III-V layer with a dopant concentration of a dopant of the first conductivity type on a surface of the III-V substrate from the vapor phase from an epitaxial gas flow, fed into the reaction chamber and comprising the carrier gas, the first precursor, and at least one second precursor for an element of main group III, wherein during the heating from the loading temperature to the epitaxy temperature, a third precursor for a dopant of the first conductivity type is added to the initial gas flow.
    Type: Application
    Filed: December 21, 2020
    Publication date: June 24, 2021
    Applicant: AZUR SPACE SOLAR POWER GMBH
    Inventors: Clemens WAECHTER, Gregor KELLER
  • Publication number: 20210193465
    Abstract: A vapor phase epitaxy method of growing a III-V layer with a doping that changes from a first conductivity type to a second conductivity type on a surface of a substrate or a preceding layer in a reaction chamber from the vapor phase from an epitaxial gas flow comprising a carrier gas, at least one first precursor for an element from main group III, and at least one second precursor for an element from main group V, wherein when a first growth height is reached, a first initial doping level of the first conductivity type is set by means of a ratio of a first mass flow of the first precursor to a second mass flow of the second precursor in the epitaxial gas flow, the first initial doping level is then reduced to a second initial doping level of the first or low second conductivity type.
    Type: Application
    Filed: December 21, 2020
    Publication date: June 24, 2021
    Applicant: AZUR SPACE SOLAR POWER GMBH
    Inventors: Clemens WAECHTER, Gregor KELLER, Daniel FUHRMANN
  • Publication number: 20200395495
    Abstract: A stacked multi-junction solar cell comprising a stack composed of a bottom subcell, at least one middle subcell, and a top subcell, wherein each subcell has an emitter and a base at least the top subcell is made of a III-V semiconductor material or includes a III-V semiconductor material, and the emitter of the top subcell includes a superlattice.
    Type: Application
    Filed: September 1, 2020
    Publication date: December 17, 2020
    Applicant: AZUR SPACE SOLAR POWER GMBH
    Inventors: Daniel FUHRMANN, Gregor KELLER, Rosalinda VAN LEEST