Patents by Inventor Lars Knoll

Lars Knoll 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: 20240170566
    Abstract: A power semiconductor device (1) is provided, comprising a drift layer (2) of a first conductivity type, at least two well regions (3) of a second conductivity type being different from the first conductivity type, and at least one intermediate region (4), wherein the at least two well regions (3) and the at least one intermediate region (4) are provided within the drift layer (2) at a first side, the at least one intermediate region (4) is provided between the at least two well regions (3), and the at least one intermediate region (4) comprises at least one first doped region (5) of the first conductivity type and at least one second doped region (6) of the second conductivity type.
    Type: Application
    Filed: February 18, 2022
    Publication date: May 23, 2024
    Inventors: Andrei MIHAILA, Munaf RAHIMO, Lars KNOLL, Marco BELLINI
  • Patent number: 11967616
    Abstract: Disclosed is a vertical silicon carbide power MOSFET with a 4H-SiC substrate of n+-type as drain and a 4H-Si C epilayer of n?-type, epitaxially grown on the 4H-SiC substrate acting as drift region and a source region of p++-type, a well region of p-type, a channel region of p-type and a contact region of n++-type implanted into the drift region and a metal gate insulated from the source and drift region by a gate-oxide. A high mobility layer with a vertical thickness in a range 0.1 nm to 50 nm exemplarily in the range of 0.5 nm to 10 nm is provided at the interface between the 4H-SiC epilayer and the gate-oxide.
    Type: Grant
    Filed: October 22, 2019
    Date of Patent: April 23, 2024
    Assignee: Hitachi Energy Ltd
    Inventors: Stephan Wirths, Andrei Mihaila, Lars Knoll
  • Publication number: 20240096937
    Abstract: A power semiconductor device and method for production thereof is specified involving an electrode, a base layer of a first conductivity type provided on the electrode, at least one contact layer provided on the base layer, a gate contact provided on the base layer and on the at least one contact layer, an insulation layer between the gate contact and the base layer and between the at least one contact layer and the gate contact, and at least one zone of a second conductivity type within the base layer, wherein the at least one zone is constructed and arranged to shift away a peak electric field generated in the base layer from the insulation layer between the gate contact and the base layer.
    Type: Application
    Filed: December 1, 2021
    Publication date: March 21, 2024
    Inventors: Marco BELLINI, Lars KNOLL, Gianpaolo ROMANO, Yulieth ARANGO
  • Publication number: 20240079454
    Abstract: A silicon carbide power device having a low on-resistance Ron and a method for manufacturing the same are provided. The silicon carbide power device comprises a first conductivity-type substrate, a plurality of silicon carbide layer stacks, a continuous insulating layer and a gate electrode layer. Each silicon carbide layer stack comprises the following layers stacked on the substrate: a first conductivity-type drain layer, a second conductivity-type channel layer and a first conductivity-type source layer. A plurality of first insulating layer portions laterally cover and surround at least the drain layer and the channel layer of each silicon carbide layer stack. Each point of each channel layer is laterally sandwiched between two opposing portions of the gate electrode layer, wherein the two opposing portions have a distance (d) of less than 2 ?m along a straight line extending through that point of that channel layer.
    Type: Application
    Filed: December 2, 2021
    Publication date: March 7, 2024
    Inventors: Stephan WIRTHS, Lars KNOLL
  • Publication number: 20240055495
    Abstract: Semiconductor device having first and second main electrodes with gate electrode layer inbetween, semiconductor layer stack between and in electrical contact with the first and second main electrodes having differently doped semiconductor layers. At least two semiconductor layers differ in their conductivity type and/or their doping concentration. Pillar-shaped or fin-shaped regions run through the gate electrode layer, each having a contact layer arranged at the first main electrode with a first doping concentration and a first conductivity type. Each contact layer extends to a side of the gate electrode layer facing the first main electrode, the contact layers of adjacent pillar-shaped or fin-shaped regions merge on the side of the gate electrode layer facing the first main electrode so that the contact layers of adjacent pillar-shaped or fin-shaped regions are arranged continuously on the side of the gate electrode layer facing the first main electrode.
    Type: Application
    Filed: December 20, 2021
    Publication date: February 15, 2024
    Inventors: Stephan WIRTHS, Lars KNOLL, Andrei Amadeus MIHAILA
  • Patent number: 11888037
    Abstract: A power semiconductor device includes a wide-bandgap semiconductor layer having an active region and a termination region that laterally surrounds the active region. The wide-bandgap semiconductor layer has a first recess that is recessed from the first main side in the termination region and surrounds the active region and a second recess that is recessed from the first main side in the active region and is filled with an insulating material. A depth of the second recess is the same as a depth of the first recess. A field plate on the first main side of the wide-bandgap semiconductor layer exposes a first portion of the wide-bandgap semiconductor layer in the termination region.
    Type: Grant
    Filed: March 5, 2019
    Date of Patent: January 30, 2024
    Assignee: Hitachi Energy Ltd
    Inventors: Andrei Mihaila, Lars Knoll, Lukas Kranz
  • Publication number: 20240021670
    Abstract: A power semiconductor device (1) comprising a semiconductor body (2) extending in a vertical direction between a first main surface (21) and a second main surface (22), a trench (4) extending from the first main surface (21) into the semiconductor body (2) in the vertical direction, and an insulated trench gate electrode (3) that is formed on the first main surface (21) and extends into the trench (4) is specified, wherein the trench (4) is subdivided along a main extension direction of the trench (4) in a plurality of segments (41) and the insulated trench gate electrode (3) continuously extends over the plurality of segments (41).
    Type: Application
    Filed: November 30, 2021
    Publication date: January 18, 2024
    Inventors: Marco BELLINI, Lars KNOLL, Gianpaolo ROMANO
  • Publication number: 20240021542
    Abstract: In at least one embodiment, the power semiconductor device (1) comprises a semiconductor body (2), and a protection layer (3) at the semiconductor body (2), wherein the protection layer (3) comprises a material having a surface energy of at most 0.1 mJ/m2, and the protection layer (3) comprises a geometric structuring (33) having a feature size (F) of at least 0.04 ?m and of at most 0.1 mm, seen in top view of the protection layer (3).
    Type: Application
    Filed: November 5, 2020
    Publication date: January 18, 2024
    Inventors: Marco BELLINI, Lars KNOLL, Jürgen SCHUDERER, Oriol LOPEZ SANCHEZ
  • Publication number: 20230411510
    Abstract: In one embodiment, the power field-effect transistor (1) comprises: at least two source regions (21) at a top side (20) of a semiconductor body (2), a drain region (22) at a back side (23) of the semiconductor body (2), at least two charge barrier regions (24) in the semiconductor body (2) so that electrically between each one of the source regions (21) and the drain region (22) there is one of the charge barrier regions (24), and a gate electrode (3) located in a trench (4) in the semiconductor body (2), and the charge barrier regions (24) are located adjacent to the trench (4), wherein, next to the trench (4) and seen in a first plane (A) perpendicular with the top side (21) and a main elongation direction (L) of the trench (4), the top side (21) is formed only by the source regions (21).
    Type: Application
    Filed: November 4, 2020
    Publication date: December 21, 2023
    Inventors: Stephan WIRTHS, Lars KNOLL, Lukas KRANZ
  • Publication number: 20230411514
    Abstract: In at least one embodiment, the power semiconductor device 1) involves a semiconductor body (2), at least one source region (21) in the semiconductor body (2), a gate electrode (3) at the semiconductor body (2), a gate insulator (4, 41, 42) between the semiconductor body (2) and the gate electrode (3), and at least one well region (22) at the at least one source region (21) and at the gate insulator (4, 41, 42), wherein the gate insulator (4, 41, 42) has a varying dielectric capacitance, the dielectric capacitance is in each case a quotient of a dielectric constant and of a geometric thickness of the gate insulator (4, 41, 42) at a specific location thereof, and the dielectric capacitance is larger at the at least one well region (22) than in remaining regions of the gate insulator (4, 42).
    Type: Application
    Filed: August 30, 2023
    Publication date: December 21, 2023
    Inventors: Gianpaolo ROMANO, Lars KNOLL, Yulieth ARANGO, Stephan WIRTHS, Andrei MIHAILA
  • Publication number: 20230369408
    Abstract: A power semiconductor device is provided. In an embodiment, the power semiconductor device comprises a source region, a channel region in the semiconductor body, and a gate electrode at the channel region. The gate electrode is electrically insulated from the semiconductor body. The channel region is of a second conductivity type different from the first conductivity type. The channel region comprises a first dopant having an activation energy of at most 0.15 eV, and a second dopant having an activation energy of at least 0.3 eV.
    Type: Application
    Filed: November 6, 2020
    Publication date: November 16, 2023
    Inventors: Marco BELLINI, Jan VOBECKY, Lars KNOLL, Gianpaolo ROMANO, Giovanni ALFIERI
  • Publication number: 20230327014
    Abstract: A power semiconductor device comprises a drift layer of a first conductivity type, a source layer of the first conductivity type on the drift layer, with an insulated trench gate electrode which extends through the source layer into the drift layer, and an implant layer of a second conductivity type different than the first conductivity type with a homogeneous doping region having a doping variation of at most 8%. The homogeneous doping region is arranged between the source layer and the drift layer and has a homogeneous doping region thickness of at least 150 nm. A method is provided for producing a power semiconductor device with an insulated trench gate electrode.
    Type: Application
    Filed: October 8, 2021
    Publication date: October 12, 2023
    Inventors: Marco BELLINI, Lars KNOLL
  • Publication number: 20230187525
    Abstract: An insulated gate structure includes a wide bandgap material layer having a channel region of a first conductivity type. A gate insulating layer is arranged directly on the channel region and has a first nitride layer that is arranged directly on the channel region. The gate insulating layer has a concentration of carbon atoms that is less than 1018 atoms/cm?3 at a distance of 3 nm from an interface between the wide bandgap material layer and the first nitride layer. An electrically conductive gate electrode layer overlies the gate insulating layer so that the gate electrode layer is separated from the wide bandgap material layer by the gate insulating layer.
    Type: Application
    Filed: February 25, 2021
    Publication date: June 15, 2023
    Inventors: Lars Knoll, Stephan Wirths, Andrei Mihaila
  • Publication number: 20220320290
    Abstract: A silicon carbide (SiC) planar transistor device includes a SiC semiconductor substrate of a first charge type, a SiC epitaxial layer of the first charge type formed at a top surface of the SiC semiconductor substrate, a source structure of the first charge type formed at a top surface of the SiC epitaxial layer, a drain structure of the first charge type formed at a bottom surface of the SiC semiconductor substrate, a gate structure comprising a gate runner and a gate dielectric that covers at least part of the source structure and the gate runner, and a channel region of a second charge type located in vertical direction below the gate structure and adjacent to the source structure. The channel can be formed by performing a plurality of implantation steps so that the channel region comprises a first region and a second region.
    Type: Application
    Filed: July 31, 2020
    Publication date: October 6, 2022
    Applicant: Hitachi Energy Switzerland AG
    Inventors: Marco Bellini, Lars Knoll
  • Publication number: 20220302309
    Abstract: A SiC transistor device includes a SiC semiconductor substrate, a SiC epitaxial layer formed on the top surface of the SiC semiconductor substrate, a source structure formed in the top surface of the SiC epitaxial layer, a source contact structure electrically coupled to the top surface of the source structure, and a gate structure that includes a gate dielectric, a metal gate, and a gate insulation. A first backside metal contact is formed on the bottom surface of the SiC semiconductor substrate, a stress inducing layer is formed on the first backside metal contact, and a second backside metal contact is formed on the stress inducing layer.
    Type: Application
    Filed: August 7, 2020
    Publication date: September 22, 2022
    Inventors: Stephan Wirths, Lars Knoll
  • Publication number: 20220278205
    Abstract: A silicon carbide transistor device includes a silicon carbide semiconductor and a silicon carbide epitaxial layer formed at a top surface of the substrate. A source structure is formed in a top surface of the silicon carbide epitaxial layer and includes a p-well region, an n-type source region and a p-type contact region. A source contact structure is formed over and electrically connected to a top surface of the source structure. A planar gate structure includes a gate dielectric and a gate runner adjacent a p-type channel region. The gate dielectric covers the channel region, at least part of the source structure and at least part of the source contact structure. The gate runner is electrically insulated from the channel region and the source structure and the source contact structure by the gate dielectric and overlaps the channel region.
    Type: Application
    Filed: July 31, 2020
    Publication date: September 1, 2022
    Inventors: Marco Bellini, Lars Knoll, Stephan Wirths
  • Patent number: 11302811
    Abstract: A silicon carbide power device, e.g., a vertical power MOSFET or an IGBT, includes a silicon carbide wafer. A first stressor and a second stressor are arranged in the silicon carbide wafer at a first main side. A first channel region, a first portion of a drift layer and a second channel region are laterally arranged between the first stressor and the second stressor in a second lateral direction parallel to the first main side and perpendicular to the first lateral direction. A stress can be introduced by the first stressor and the second stressor in the first channel region and in the second channel region.
    Type: Grant
    Filed: December 16, 2019
    Date of Patent: April 12, 2022
    Assignee: Hitachi Energy Switzerland AG
    Inventors: Marco Bellini, Lars Knoll, Lukas Kranz
  • Publication number: 20220045213
    Abstract: A silicon carbide power device, e.g., a vertical power MOSFET or an IGBT, includes a silicon carbide wafer. A first stressor and a second stressor are arranged in the silicon carbide wafer at a first main side. A first channel region, a first portion of a drift layer and a second channel region are laterally arranged between the first stressor and the second stressor in a second lateral direction parallel to the first main side and perpendicular to the first lateral direction. A stress can be introduced by the first stressor and the second stressor in the first channel region and in the second channel region.
    Type: Application
    Filed: December 16, 2019
    Publication date: February 10, 2022
    Inventors: Marco Bellini, Lars Knoll, Lukas Kranz
  • Publication number: 20220028976
    Abstract: Disclosed is a vertical silicon carbide power MOSFET with a 4H-SiC substrate of n+-type as drain and a 4H-Si C epilayer of n?-type, epitaxially grown on the 4H-SiC substrate acting as drift region and a source region of p++-type, a well region of p-type, a channel region of p-type and a contact region of n++-type implanted into the drift region and a metal gate insulated from the source and drift region by a gate-oxide. A high mobility layer with a vertical thickness in a range 0.1 nm to 50 nm exemplarily in the range of 0.5 nm to 10 nm is provided at the interface between the 4H-SiC epilayer and the gate-oxide.
    Type: Application
    Filed: October 22, 2019
    Publication date: January 27, 2022
    Inventors: Stephan Wirths, Andrei Mihaila, Lars Knoll
  • Patent number: 11031473
    Abstract: A power semiconductor device includes a semiconductor wafer having a first main side surface and a second main side surface. The semiconductor wafer includes a first semiconductor layer having a first conductivity type and a plurality of columnar or plate-shaped first semiconductor regions extending in the first semiconductor layer between the first main side surface and the second main side surface in a vertical direction perpendicular to the first main side surface and the second main side surface. The first semiconductor regions have a second conductivity type, which is different from the first conductivity type. Therein, the first semiconductor is a layer of hexagonal silicon carbide. The first semiconductor regions are regions of 3C polytype silicon carbide.
    Type: Grant
    Filed: September 3, 2019
    Date of Patent: June 8, 2021
    Assignee: ABB POWER GRIDS SWITZERLAND AG
    Inventors: Friedhelm Bauer, Lars Knoll, Marco Bellini, Renato Minamisawa, Umamaheswara Vemulapati