Patents Assigned to Wolfspeed, Inc.
  • Patent number: 11936368
    Abstract: The present disclosure relates to a power module with a power path extending through a first field-effect transistor (FET) and a second FET. A primary conductive structure connecting the first FET and the second FET in series provides a primary parasitic inductor within the power path. A first secondary conductive structure connected to both a gate and a source of the first FET provides a first secondary parasitic inductor within a first gate path, and a second secondary conductive structure connected to both a gate and a source of the second FET provides a second secondary parasitic inductor within a second gate path. The first secondary conductive structure and the second secondary conductive structure are configured such that mutual coupling between the first secondary parasitic inductor and the primary parasitic inductor and mutual coupling between the second secondary parasitic inductor and the primary parasitic inductor are substantially symmetrical.
    Type: Grant
    Filed: June 26, 2022
    Date of Patent: March 19, 2024
    Assignee: WOLFSPEED, INC.
    Inventors: Blake Whitmore Nelson, Brian DeBoi, Daniel John Martin
  • Patent number: 11935879
    Abstract: A transistor package that includes a metal submount; a transistor die mounted on said metal submount; a surface mount IPD component that includes a dielectric substrate; and the dielectric substrate mounted on said metal submount. Additionally, the dielectric substrate includes one of the following: an irregular shape, a non-square shape, and a nonrectangular shape.
    Type: Grant
    Filed: June 9, 2021
    Date of Patent: March 19, 2024
    Assignee: Wolfspeed, Inc.
    Inventors: Eng Wah Woo, Samantha Cheang, Kok Meng Kam, Marvin Mabell, Haedong Jang, Alexander Komposch
  • Patent number: 11929428
    Abstract: An apparatus includes a substrate; a group III-Nitride barrier layer; a source electrically coupled to the group III-Nitride barrier layer; a gate on the group III-Nitride barrier layer; a drain electrically coupled to the group III-Nitride barrier layer; a p-region being arranged at or below the group III-Nitride barrier layer; and a recovery enhancement circuit configured to reduce an impact of an overload received by the gate. Additionally, at least a portion of the p-region is arranged vertically below at least one of the following: the source, the gate, an area between the gate and the drain.
    Type: Grant
    Filed: May 17, 2021
    Date of Patent: March 12, 2024
    Assignee: Wolfspeed, Inc.
    Inventors: Thomas J. Smith, Jr., Saptharishi Sriram, Charles W. Richards, IV
  • Patent number: 11929420
    Abstract: A semiconductor device includes a semiconductor layer structure that comprises silicon carbide, a gate dielectric layer on the semiconductor layer structure, the gate dielectric layer including a base gate dielectric layer that is on the semiconductor layer structure and a capping gate dielectric layer on the base gate dielectric layer opposite the semiconductor layer structure, and a gate electrode on the gate dielectric layer opposite the semiconductor layer structure. A dielectric constant of the capping gate dielectric layer is higher than a dielectric constant of the base gate dielectric layer.
    Type: Grant
    Filed: February 10, 2022
    Date of Patent: March 12, 2024
    Assignee: Wolfspeed, Inc.
    Inventor: Daniel J. Lichtenwalner
  • Patent number: 11923344
    Abstract: A power module is provided with a substrate, power devices, and a housing. The power devices are mounted on device pads of the substrate and arranged to provide a power circuit having a first input, a second input, and at least one output. First and second power terminals provide first and second inputs for the power circuit. At least one output power terminal provides at least one output. The housing encompasses the substrate, the power devices, and portions of the first and second input power terminals as well as the at least one output power terminal. The first and second input power terminals extend out of a first side of the housing, and the at least one output power terminal extends out of a second side of the housing, the first side being opposite the second side.
    Type: Grant
    Filed: November 11, 2021
    Date of Patent: March 5, 2024
    Assignee: WOLFSPEED, INC.
    Inventors: Brice McPherson, Shashwat Singh, Roberto M. Schupbach
  • Patent number: 11911842
    Abstract: A crystalline material processing method includes forming subsurface laser damage at a first average depth position to form cracks in the substrate interior propagating outward from at least one subsurface laser damage pattern, followed by imaging the substrate top surface, analyzing the image to identify a condition indicative of presence of uncracked regions within the substrate, and taking one or more actions responsive to the analyzing. One potential action includes changing an instruction set for producing subsequent laser damage formation (at second or subsequent average depth positions), without necessarily forming additional damage at the first depth position. Another potential action includes forming additional subsurface laser damage at the first depth position.
    Type: Grant
    Filed: January 10, 2022
    Date of Patent: February 27, 2024
    Assignee: WOLFSPEED, INC.
    Inventors: Matthew Donofrio, John Edmond, Harshad Golakia, Eric Mayer
  • Patent number: 11908823
    Abstract: A packaged semiconductor device includes a first bond pad, a second bond pad, a first bond wire that includes a first end bonded to the first bond pad and a second end bonded to the second bond pad, and a second bond wire that includes a first end that is electrically connected to the first bond pad and a second end that is electrically connected to the second bond pad. The first end of the second bond wire is bonded to the first end of the first bond wire. A method of bonding a bond wire includes bonding a first end of a first bond wire to a contact surface of a first bond pad and bonding a first end of a second bond wire to a surface of the first end of the first bond wire.
    Type: Grant
    Filed: January 11, 2021
    Date of Patent: February 20, 2024
    Assignee: Wolfspeed, Inc.
    Inventors: Erwin Orejola, Brian Condie, Ulf Andre
  • Patent number: 11901181
    Abstract: A method for removing a portion of a crystalline material (e.g., SiC) substrate includes joining a surface of the substrate to a rigid carrier (e.g., >800 ?m thick), with a subsurface laser damage region provided within the substrate at a depth relative to the surface. Adhesive material having a glass transition temperature above 25° C. may bond the substrate to the carrier. The crystalline material is fractured along the subsurface laser damage region to produce a bonded assembly including the carrier and a portion of the crystalline material. Fracturing of the crystalline material may be promoted by (i) application of a mechanical force proximate to at least one carrier edge to impart a bending moment in the carrier; (ii) cooling the carrier when the carrier has a greater coefficient of thermal expansion than the crystalline material; and/or (iii) applying ultrasonic energy to the crystalline material.
    Type: Grant
    Filed: April 8, 2021
    Date of Patent: February 13, 2024
    Assignee: WOLFSPEED, INC.
    Inventors: Matthew Donofrio, John Edmond, Hua-Shuang Kong, Elif Balkas
  • Patent number: 11894455
    Abstract: A precursor for a vertical semiconductor device is provided with a substrate, a drift region over the substrate, and an upper precursor region over the drift region. The top surface of the precursor is substantially planar, and the substrate and the drift region are doped with a first dopant of a first polarity. In a first embodiment, a series of implants with a second dopant is provided in the upper precursor region via the top surface to form each of at least two gate regions such that each implant of the series of implants is provided at a different depth below the top surface. In a second embodiment, a series of implants with the first dopant is provided in the upper precursor region via the top surface to form a channel region that has at least a portion between two gate regions.
    Type: Grant
    Filed: September 22, 2021
    Date of Patent: February 6, 2024
    Assignee: Wolfspeed, Inc.
    Inventors: Daniel Jenner Lichtenwalner, Sei-Hyung Ryu, Arman Ur Rashid
  • Patent number: 11887945
    Abstract: The present disclosure relates to a semiconductor device with isolation and/or protection structures. A semiconductor device can include a substrate, a first transistor and a second transistor, wherein the first transistor and the second transistor are formed on the substrate, and an isolation structure formed on the substrate. The isolation structure can be formed on the substrate between the first transistor and the second transistor. The isolation structure can be configured to isolate the first transistor and the second transistor.
    Type: Grant
    Filed: September 30, 2020
    Date of Patent: January 30, 2024
    Assignee: WOLFSPEED, INC.
    Inventors: Lei Zhao, Fabian Radulescu
  • Patent number: 11887953
    Abstract: A package for power electronics includes a power substrate, a number of power semiconductor die, and a Kelvin connection contact. Each one of the power semiconductor die are on the power substrate and include a first power switching pad, a second power switching pad, a control pad, a semiconductor structure, and a Kelvin connection pad. The semiconductor structure is between the first power switching pad, the second power switching pad, and the control pad, and is configured such that a resistance of a power switching path between the first power switching pad and the second power switching pad is based on a control signal provided at the control pad. The Kelvin connection pad is coupled to the power switching path. The Kelvin connection contact is coupled to the Kelvin connection pad of each one of the power semiconductor die via a Kelvin conductive trace on the power substrate.
    Type: Grant
    Filed: June 21, 2021
    Date of Patent: January 30, 2024
    Assignee: Wolfspeed, Inc.
    Inventors: Brice McPherson, Daniel Martin, Jennifer Stabach
  • Patent number: 11888392
    Abstract: A power converter module includes an active metal braze (AMB) substrate, power converter circuitry, and a housing. The AMB substrate includes an aluminum nitride base layer, a first conductive layer on a first surface of the aluminum nitride base layer, and a second conductive layer on a second surface of the aluminum nitride base layer opposite the first surface. The power converter circuitry includes a number of silicon carbide switching components coupled to one another via the first conductive layer. The housing is over the power converter circuitry and the AMB substrate. By using an AMB substrate with an aluminum nitride base layer, the thermal dissipation characteristics of the power converter module may be substantially improved while maintaining the structural integrity of the power converter module.
    Type: Grant
    Filed: April 17, 2020
    Date of Patent: January 30, 2024
    Assignee: Wolfspeed, Inc.
    Inventors: Mrinal K. Das, Adam Barkley, Henry Lin, Marcelo Schupbach
  • Patent number: 11881464
    Abstract: A radio frequency (RF) power amplifier device package includes a substrate and a first die attached to the substrate at a bottom surface of the first die. The first die includes top gate or drain contacts on a top surface of the first die opposite the bottom surface. At least one of the top gate or drain contacts is electrically connected to a respective bottom gate or drain contact on the bottom surface of the first die by a respective conductive via structure. An integrated interconnect structure, which is on the first die opposite the substrate, includes a first contact pad on the top gate contact or the top drain contact of the first die, and at least one second contact pad connected to a package lead, a contact of a second die, impedance matching circuitry, and/or harmonic termination circuitry.
    Type: Grant
    Filed: March 24, 2021
    Date of Patent: January 23, 2024
    Assignee: Wolfspeed, Inc.
    Inventors: Basim Noori, Marvin Marbell, Kwangmo Chris Lim, Qianli Mu
  • Patent number: 11869948
    Abstract: Strategic placement and patterning of electrodes, vias, and metal runners can significantly reduce strain in a power semiconductor die. By modifying the path defining electrodes, vias, and metal runners, as well as patterning the material layers thereof, strain can be better managed to increase reliability of a power semiconductor die.
    Type: Grant
    Filed: February 17, 2021
    Date of Patent: January 9, 2024
    Assignee: Wolfspeed, Inc.
    Inventors: Daniel Jenner Lichtenwalner, Edward Robert Van Brunt, Thomas E. Harrington, III, Shadi Sabri, Brett Hull, Brice McPherson, Joe W. McPherson
  • Patent number: 11869964
    Abstract: A transistor device includes a semiconductor epitaxial layer structure including a channel layer and a barrier layer on the channel layer, wherein the barrier layer has a higher bandgap than the channel layer. A modified access region is provided at an upper surface of the barrier layer opposite the channel layer. The modified access region includes a material having a lower surface barrier height than the barrier layer. A source contact and a drain contact are formed on the barrier layer, and a gate contact is formed between source contact and the drain contact.
    Type: Grant
    Filed: May 20, 2021
    Date of Patent: January 9, 2024
    Assignee: Wolfspeed, Inc.
    Inventors: Kyoung-Keun Lee, Fabian Radulescu, Scott Sheppard
  • Patent number: 11863130
    Abstract: RF transistor amplifiers include a Group III nitride-based RF transistor amplifier die that includes a semiconductor layer structure, a conductive source via that is connected to a source region of the Group III nitride-based RF transistor amplifier die, the conductive source via extending through the semiconductor layer structure, and an additional conductive via that extends through the semiconductor layer structure. A first end of the additional conductive via is connected to a first external circuit and a second end of the additional conductive via that is opposite the first end is connected to a first matching circuit.
    Type: Grant
    Filed: March 29, 2021
    Date of Patent: January 2, 2024
    Assignee: Wolfspeed, Inc.
    Inventors: Basim Noori, Marvin Marbell, Qianli Mu, Kwangmo Chris Lim, Michael E. Watts, Mario Bokatius, Jangheon Kim
  • Patent number: 11862719
    Abstract: An apparatus includes a substrate. The apparatus further includes a group III-nitride buffer layer on the substrate; a group III-nitride barrier layer on the group III-nitride buffer layer, the group III-nitride barrier layer including a higher bandgap than a bandgap of the group III-nitride buffer layer. The apparatus further includes a source electrically coupled to the group III-nitride barrier layer; a gate electrically coupled to the group III-nitride barrier layer; a drain electrically coupled to the group III-nitride barrier layer; and a p-region being at least one of the following: in the substrate or on the substrate below said group III-nitride barrier layer.
    Type: Grant
    Filed: December 16, 2020
    Date of Patent: January 2, 2024
    Assignee: Wolfspeed, Inc.
    Inventors: Saptharishi Sriram, Thomas Smith, Alexander Suvorov, Christer Hallin
  • Patent number: 11843061
    Abstract: A power semiconductor device has a semiconductor layer structure that includes a silicon carbide drift region having a first conductivity type, first and second wells in the silicon carbide drift region that are doped with dopants having a second conductivity type, and a JFET region between the first and second wells. The first and second wells each include a main well and a side well that is between the main well and the JFET region, and each side well includes a respective channel region. A doping concentration of the JFET region exceeds a doping concentration of the silicon carbide drift region, and a minimum width of an upper portion of the JFET region is greater than a minimum width of a lower portion of the JFET region.
    Type: Grant
    Filed: August 27, 2020
    Date of Patent: December 12, 2023
    Assignee: Wolfspeed, Inc.
    Inventors: Kijeong Han, Joohyung Kim, Sei-Hyung Ryu
  • Patent number: 11842997
    Abstract: An integrated circuit device includes a radio frequency transistor amplifier die having a first surface, a second surface, a semiconductor layer structure that is between the first and second surfaces and includes a plurality of transistor cells adjacent the first surface, and terminals coupled to the transistor cells. At least one passive electronic component is provided on the second surface of the die and is electrically connected to at least one of the terminals, for example, by at least one conductive via. One or more conductive pillar structures may protrude from the first surface of the die to provide electrical connections to one or more of the terminals.
    Type: Grant
    Filed: March 21, 2022
    Date of Patent: December 12, 2023
    Assignee: Wolfspeed, Inc.
    Inventors: Terry Alcorn, Daniel Namishia, Fabian Radulescu
  • Patent number: RE49913
    Abstract: A power metal-oxide-semiconductor field-effect transistor (MOSFET) includes a substrate, a drift layer over the substrate, and a spreading layer over the drift layer. The spreading layer includes a pair of junction implants separated by a junction gate field effect (JFET) region. A gate oxide layer is on top of the spreading layer. The gate contact is on top of the gate oxide layer. Each one of the source contacts are on a portion of the spreading layer separate from the gate oxide layer and the gate contact. The drain contact is on the surface of the substrate opposite the drift layer.
    Type: Grant
    Filed: October 26, 2020
    Date of Patent: April 9, 2024
    Assignee: Wolfspeed, Inc.
    Inventors: Vipindas Pala, Anant Kumar Agarwal, Lin Cheng, Daniel Jenner Lichtenwalner, John Williams Palmour