Patents by Inventor Sei-Hyung Ryu

Sei-Hyung Ryu 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: 20250254909
    Abstract: A power semiconductor device includes a semiconductor structure comprising an active region, a plurality of gates that extend in a first direction in or on the active region of the semiconductor structure, at least one integrated polysilicon device in or on the semiconductor structure adjacent the active region, and a gate connector electrically connecting the plurality of gates. The gate connector is in or on the semiconductor structure between the at least one integrated polysilicon device and the plurality of gates. The at least one integrated polysilicon device is electrically isolated from the gate connector devoid of an inter-polysilicon dielectric layer therebetween. Related devices and fabrication methods are also discussed.
    Type: Application
    Filed: February 1, 2024
    Publication date: August 7, 2025
    Inventors: Woongsun Kim, Naeem Islam, Madankumar Sampath, Sei-Hyung Ryu
  • Patent number: 12376319
    Abstract: A power semiconductor device includes a semiconductor layer structure comprising a drift region of a first conductivity type, and a gate trench extending into the drift region. The gate trench includes sidewalls and a bottom surface therebetween. A bottom shielding structure of a second conductivity type is provided under the bottom surface of the gate trench. First and second support shielding structures of the second conductivity type extend into the drift region on opposing sides of the gate trench and are spaced apart from the sidewalls thereof. A material composition, distance of extension into the drift region relative to a surface of the semiconductor layer structure, and/or dopant concentration of the bottom shielding structure may be different from that of the first and second support shielding structures. Related devices and fabrication methods are also discussed.
    Type: Grant
    Filed: March 24, 2022
    Date of Patent: July 29, 2025
    Assignee: WOLFSPEED, INC.
    Inventors: Woongsun Kim, Daniel Jenner Lichtenwalner, Naeem Islam, Madankumar Sampath, Sei-Hyung Ryu
  • Publication number: 20250241040
    Abstract: A semiconductor device comprises a semiconductor layer structure that has a gate trench therein and a source metallization layer on the semiconductor layer structure. The semiconductor layer structure comprises a drift region having a first conductivity type, a trench shield that has a second conductivity type, the trench shield positioned underneath the gate trench, and a trench shield connection pattern that has the second conductivity type, the trench shield connection pattern electrically connecting the trench shield to the source metallization layer, where the trench shield connection pattern extends deeper into the semiconductor layer structure than the trench shield.
    Type: Application
    Filed: January 19, 2024
    Publication date: July 24, 2025
    Inventors: Madankumar Sampath, Woongsun Kim, Naeem Islam, Sei-Hyung Ryu
  • Publication number: 20250169166
    Abstract: A semiconductor device includes a device active region comprising a first well, at least a portion of the first well being part of a first metal-oxide-semiconductor field-effect transistor (MOSFET), and a sensor region comprising a second well, at least a portion of the second well being part of a second MOSFET configured to mirror a current in the first MOSFET. A distance between an outer edge of the second well and an inner edge of the first well is constant or the distance decreases approaching one or more vertices of the second well.
    Type: Application
    Filed: November 16, 2023
    Publication date: May 22, 2025
    Inventors: Madankumar Sampath, Sei-Hyung Ryu
  • Publication number: 20250169128
    Abstract: A semiconductor device comprises a semiconductor layer structure comprising a drift region having a first conductivity type, a well region having a second conductivity type on the drift region, and a first JFET region having the first conductivity type, and a gate trench extending into the semiconductor layer structure. An upper surface of the first JFET region is positioned below the gate trench. A first conductivity dopant concentration of the first JFET region exceeds a first conductivity dopant concentration of the drift region.
    Type: Application
    Filed: November 16, 2023
    Publication date: May 22, 2025
    Inventors: Naeem Islam, Woongsun Kim, Madankumar Sampath, Sei-Hyung Ryu
  • Publication number: 20250169105
    Abstract: A semiconductor device includes a semiconductor layer structure comprising a junction field-effect transistor (JFET) region of a first conductivity type, a well region of a second conductivity type on the JFET region, a source region of the first conductivity type on the well region and a plurality of support shields of the second conductivity type. The support shields are spaced apart from one another in a first direction parallel to an upper surface of the semiconductor layer structure and extend through the source region, the well region and the JFET region. The semiconductor device further includes a trenched gate structure formed in the semiconductor layer structure between a pair of adjacent support shields. Edges of at least two of the JFET region, the well region and the source region are aligned in a second direction perpendicular to the first direction.
    Type: Application
    Filed: November 20, 2023
    Publication date: May 22, 2025
    Inventors: Woongsun Kim, Naeem Islam, Madankumar Sampath, Sei-Hyung Ryu
  • Publication number: 20250159948
    Abstract: A power semiconductor device includes a semiconductor structure having a drift region of a first conductivity type. Gate trenches respectively comprising sidewalls and a bottom surface therebetween extend in a first direction in the semiconductor structure, and support shielding structures of a second conductivity type extend in the first direction in the semiconductor structure spaced apart from the sidewalls of the gate trenches. At least two of the support shielding structures are between immediately adjacent pairs of the gate trenches, or at least two of the gate trenches are between immediately adjacent pairs of the support shielding structures. For example, the support shielding structures may include first and second support shielding structures that are free of the gate trenches therebetween, or the gate trenches may include first and second gate trenches that are free of the support shielding structures therebetween. Related devices and fabrication methods are also discussed.
    Type: Application
    Filed: November 14, 2023
    Publication date: May 15, 2025
    Inventors: Madankumar Sampath, Woongsun Kim, Naeem Islam, Sei-Hyung Ryu
  • Publication number: 20250142868
    Abstract: Semiconductor devices are provided that comprise a semiconductor layer structure that comprises a drift region having a first conductivity type, a channel region having a second conductivity type, and a source region having the first conductivity type. A gate trench extends into an upper surface of the semiconductor layer structure. The channel region horizontally overlaps both the gate trench and the source region.
    Type: Application
    Filed: October 26, 2023
    Publication date: May 1, 2025
    Inventors: Woongsun Kim, Naeem Islam, Madankumar Sampath, Sei-Hyung Ryu
  • Publication number: 20250142877
    Abstract: A semiconductor device comprises a silicon carbide based semiconductor layer structure that comprises a drift region having a first conductivity type and an implanted region having a second conductivity type on the drift region. First and second gate trench sections extend into the semiconductor layer structure. A first maximum depth into the semiconductor layer structure of a first portion of the implanted region that is between the first gate trench section and the second gate trench section is different than a second maximum depth into the semiconductor layer structure of a second portion of the implanted region that extends downwardly underneath the first gate trench section.
    Type: Application
    Filed: October 25, 2023
    Publication date: May 1, 2025
    Inventors: Woongsun Kim, Naeem Islam, Madankumar Sampath, Sei-Hyung Ryu
  • Patent number: 12289906
    Abstract: A vertical semiconductor device includes a substrate, a drift region over the substrate, an upper region on the drift region, a top surface over the upper region and being substantially planar, and a series of implants of a second dopant in the upper region, such that each implant of the series of implants is located at a different depth below the top surface. The series of implants forms at least two gate region. The substrate and the drift region are doped with a first dopant of a first polarity. The second dopant has a second polarity opposite that of the first polarity. At least a portion of a channel region is provided between the at least two gate regions, and a conducting gap is defined within the channel region and between opposing sidewalls of the at least two gate regions.
    Type: Grant
    Filed: January 31, 2024
    Date of Patent: April 29, 2025
    Assignee: Wolfspeed, Inc.
    Inventors: Daniel Jenner Lichtenwalner, Sei-Hyung Ryu, Arman Ur Rashid
  • Patent number: 12278284
    Abstract: Semiconductor devices and methods of forming the devices are provided. Semiconductor devices include a semiconductor layer structure comprising a trench in an upper surface thereof, a dielectric layer in a lower portion of the trench, and a gate electrode in the trench and on the dielectric layer opposite the semiconductor layer structure. The trench may include rounded upper corner and a rounded lower corner. A center portion of a top surface of the dielectric layer may be curved, and the dielectric layer may be on opposed sidewalls of the trench. The dielectric layer may include a bottom dielectric layer on a bottom surface of the trench and on lower portions of the sidewalls of the trench and a gate dielectric layer on upper portions of the sidewalls of the trench and on the bottom dielectric layer.
    Type: Grant
    Filed: March 24, 2023
    Date of Patent: April 15, 2025
    Assignee: Wolfspeed, Inc.
    Inventors: Daniel Lichtenwalner, Sei-Hyung Ryu, Naeem Islam, Woongsun Kim, Matthew N. McCain, Joe McPherson
  • Patent number: 12279448
    Abstract: Semiconductor devices and methods of forming a semiconductor device that includes a polysilicon layer that may improve device reliability and/or a functioning of the device. An example device may include a wide band-gap semiconductor layer structure including a drift region that has a first conductivity type; a plurality of gate trenches in an upper portion of the semiconductor layer structure, each gate trench having a bottom surface, a first sidewall, a second sidewall, and an upper opening; and a plurality of polysilicon layers, each polysilicon layer on the second sidewall of a respective gate trench.
    Type: Grant
    Filed: June 3, 2022
    Date of Patent: April 15, 2025
    Assignee: Wolfspeed, Inc.
    Inventors: Woongsun Kim, Daniel J. Lichtenwalner, Naeem Islam, Sei-Hyung Ryu
  • Publication number: 20250120133
    Abstract: A semiconductor device comprises a silicon carbide based semiconductor layer structure that includes a drift layer having a first conductivity type, a gate trench that extends to a first depth into an upper surface of the semiconductor layer structure, a gate electrode in the gate trench, a support shield trench that extends to a second depth into the upper surface of the semiconductor layer structure, where the second depth is less than the first depth, and a source metallization layer on the upper surface of the semiconductor layer structure and extending into the support shield trench.
    Type: Application
    Filed: October 6, 2023
    Publication date: April 10, 2025
    Inventors: Woongsun Kim, Naeem Islam, Madankumar Sampath, Sei-Hyung Ryu
  • Publication number: 20250120119
    Abstract: A semiconductor device comprises a silicon carbide based semiconductor layer structure and a first gate trench extending into an upper portion of the semiconductor layer structure. The semiconductor layer structure comprises a drift region having a first conductivity type, a well layer having a second conductivity type, and a support shield having the second conductivity type. A width of a first segment of the support shield that is deeper in the semiconductor layer structure than the well layer and less deep in the semiconductor layer structure than a bottom of the first gate trench decreases with increasing distance from the well region.
    Type: Application
    Filed: October 6, 2023
    Publication date: April 10, 2025
    Inventors: Madankumar Sampath, Woongsun Kim, Naeem Islam, Sei-Hyung Ryu
  • Publication number: 20250107124
    Abstract: Semiconductor devices are provided. In one example, a semiconductor device includes a semiconductor structure. The semiconductor device includes a gate finger in a gate trench in the semiconductor structure. The gate trench extends a length in the semiconductor structure. The gate trench has a first portion having a first width and a second portion having a second width. The second width is different than the first width.
    Type: Application
    Filed: September 27, 2023
    Publication date: March 27, 2025
    Inventors: Woongsun Kim, S M Naeemul Islam, Madankumar Sampath, Sei-Hyung Ryu
  • Publication number: 20250089316
    Abstract: Power semiconductor devices are provided. In one example, the power semiconductor device includes a semiconductor structure includes an active region and an inactive region, the active region includes a plurality of unit cells. The power semiconductor device includes a gate structure, wherein at least a portion of the gate structure is on the inactive region. The power semiconductor device includes a first shunt contact structure at least partially on the inactive region. The power semiconductor device includes a second shunt contact structure at least partially on the inactive region. The power semiconductor device includes a balancing shunt structure at least partially on the inactive region.
    Type: Application
    Filed: September 13, 2023
    Publication date: March 13, 2025
    Inventors: Charlotte Elizabeth Jonas, Joohyung Kim, Sei-Hyung Ryu
  • Publication number: 20250072044
    Abstract: A semiconductor device comprises a silicon carbide based semiconductor layer structure that comprises an active region. A gate trench is provided in an upper portion of the semiconductor layer structure, the gate trench having a first rounded lower corner and a second rounded lower corner. A gate electrode is provided in the gate trench. Within the active region, an upper surface of the gate electrode is below or coplanar with an upper surface of the semiconductor layer structure.
    Type: Application
    Filed: August 22, 2023
    Publication date: February 27, 2025
    Inventors: Woongsun Kim, Matthew N. McCain, Naeem Islam, Madankumar Sampath, Sei-Hyung Ryu
  • Patent number: 12237412
    Abstract: Semiconductor devices, and in particular protection structures for semiconductor devices that include sensor arrangements are disclosed. A semiconductor device may include a sensor region, for example a current sensor region that occupies a portion of an overall active area of the device. The current sensor region may be configured to provide monitoring of device load currents during operation. Semiconductor devices according to the present disclosure include one or more protection structures that are configured to allow the semiconductor devices to withstand transient voltage events without device failure. A protection structure may include an insulating layer that is provided in a transition region between a device region and the sensor region of the semiconductor device. In the example of an insulated gate semiconductor device, the insulating layer of the protection structure may include a material with a greater breakdown voltage than a breakdown voltage of a gate insulating layer.
    Type: Grant
    Filed: November 3, 2020
    Date of Patent: February 25, 2025
    Assignee: Wolfspeed, Inc.
    Inventors: Edward Robert Van Brunt, Sei-Hyung Ryu
  • Patent number: 12176423
    Abstract: A power semiconductor device includes a semiconductor layer structure comprising a wide bandgap semiconductor material. The semiconductor layer structure includes a drift region of a first conductivity type and a plurality of fin structures protruding from the drift region. The fin structures comprise respective source regions of the first conductivity type and respective channel regions between the respective source regions and the drift region. Related devices and methods are also discussed.
    Type: Grant
    Filed: December 1, 2020
    Date of Patent: December 24, 2024
    Assignee: Wolfspeed, Inc.
    Inventors: Naeem Islam, Woongsun Kim, Daniel Jenner Lichtenwalner, Sei-Hyung Ryu
  • Publication number: 20240413197
    Abstract: devices and methods of forming a semiconductor device that includes a deep shielding pattern that may improve a reliability and/or a functioning of the device. An example method may include forming a wide band-gap semiconductor layer structure on a substrate, the semiconductor layer structure including a drift region that has a first conductivity type; forming a plurality of gate trenches in an upper portion of the semiconductor layer structure, the gate trenches spaced apart from each other, each gate trench having a bottom surface, a first sidewall, a second sidewall, and an upper opening; forming an obstruction over a portion of each gate trench that partially obscures the upper opening; and implanting dopants having a second conductivity type that is opposite the first conductivity type into the bottom surfaces of the gate trenches, where the dopants implanted into the bottom surface of the gate trenches form deep shielding patterns.
    Type: Application
    Filed: August 23, 2024
    Publication date: December 12, 2024
    Inventors: Daniel J. Lichtenwalner, Naeem Islam, Woongsun Kim, Sei-Hyung Ryu