Patents by Inventor Luther-King Ngwendson

Luther-King Ngwendson 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: 11569371
    Abstract: We disclose herein a gate controlled bipolar semiconductor device comprising: a collector region of a first conductivity type; a drift region of a second conductivity type located over the collector region; a body region of a first conductivity type located over the drift region; a plurality of first contact regions of a second conductivity type located above the body region and having a higher doping concentration than the body region; a second contact region of a first conductivity type located laterally adjacent to the plurality of first contact regions, the second contact region having a higher doping concentration than the body region; at least two active trenches each extending from a surface into the drift region; an emitter trench extending from the surface into the drift region; wherein each first contact region adjoins an active trench so that, in use, a channel is formed along said each active trench and within the body region; wherein the second contact region adjoins the emitter trench; and where
    Type: Grant
    Filed: May 25, 2017
    Date of Patent: January 31, 2023
    Assignees: DYNEX SEMICONDUCTOR LIMITED, ZHUZHOU CRRC TIMES ELECTRIC CO. LTD.
    Inventors: Ian Deviny, Luther-King Ngwendson, John Hutchings
  • Patent number: 11239351
    Abstract: A gate controlled semiconductor device comprising a collector region of a first conductivity type; a drift region of a second conductivity type located over the collector region; a body region of a first conductivity type located over the drift region; at least one first contact region of a second conductivity type located above the body region and having a higher doping concentration compared to the body region. The device further comprises at least one second contact region of a first conductivity type located laterally adjacent to the at least one first contact region, the at least one second contact region having a higher doping concentration than the body region. The device further comprises at least one active trench extending from a surface into the drift region, in which the at least one first contact region adjoins the at least one active trench so that, in use, a channel region is formed along said at least one active trench and within the body region.
    Type: Grant
    Filed: January 4, 2018
    Date of Patent: February 1, 2022
    Assignee: DYNEX SEMICONDUCTOR LIMITED
    Inventors: Luther-King Ngwendson, Ian Deviny, John Hutchings
  • Publication number: 20200127128
    Abstract: We disclose herein a gate controlled bipolar semiconductor device comprising: a collector region of a first conductivity type; a drift region of a second conductivity type located over the collector region;a body region of a first conductivity type located over the drift region; a plurality of first contact regions of a second conductivity type located above the body region and having a higher doping concentration than the body region; a second contact region of a first conductivity type located laterally adjacent to the plurality of first contact regions, the second contact region having a higher doping concentration than the body region; at least two active trenches each extending from a surface into the drift region;an emitter trench extending from the surface into the drift region; wherein each first contact region adjoins an active trench so that, in use, a channel is formed along said each active trench and within the body region; wherein the second contact region adjoins the emitter trench; and wherein
    Type: Application
    Filed: May 25, 2017
    Publication date: April 23, 2020
    Inventors: Ian DEVINY, Luther-King NGWENDSON, John HUTCHINGS
  • Publication number: 20200091328
    Abstract: A gate controlled semiconductor device comprising a collector region of a first conductivity type; a drift region of a second conductivity type located over the collector region; a body region of a first conductivity type located over the drift region; at least one first contact region of a second conductivity type located above the body region and having a higher doping concentration compared to the body region. The device further comprises at least one second contact region of a first conductivity type located laterally adjacent to the at least one first contact region, the at least one second contact region having a higher doping concentration than the body region. The device further comprises at least one active trench extending from a surface into the drift region, in which the at least one first contact region adjoins the at least one active trench so that, in use, a channel region is formed along said at least one active trench and within the body region.
    Type: Application
    Filed: January 4, 2018
    Publication date: March 19, 2020
    Inventors: Luther-King NGWENDSON, Ian DEVINY, John HUTCHINGS
  • Patent number: 9899477
    Abstract: An edge termination structure is disclosed. The edge termination structure includes an active cell in a semiconductor wafer, an edge termination region adjacent the active cell in the semiconductor wafer, where the edge termination region includes a recessed field oxide region and a termination charge region below the recessed field oxide region. The recessed field oxide region may be thermally grown in a recess in the semiconductor wafer. A top surface of the recessed field oxide region is substantially coplanar with a top surface of the semiconductor wafer. The active cell may include at least one insulated-gate bipolar transistor surrounded by the edge termination region in the semiconductor wafer. The termination charge region has a conductivity type opposite of that of the semiconductor wafer. The termination charge region is adjacent to at least one guard ring in the semiconductor wafer.
    Type: Grant
    Filed: July 2, 2015
    Date of Patent: February 20, 2018
    Assignee: Infineon Technologies Americas Corp.
    Inventors: Russell Turner, Rajeev Krishna Vytla, Luther-King Ngwendson, Nicholas Limburn
  • Publication number: 20160020308
    Abstract: An edge termination structure is disclosed. The edge termination structure includes an active cell in a semiconductor wafer, an edge termination region adjacent the active cell in the semiconductor wafer, where the edge termination region includes a recessed field oxide region and a termination charge region below the recessed field oxide region. The recessed field oxide region may be thermally grown in a recess in the semiconductor wafer. A top surface of the recessed field oxide region is substantially coplanar with a top surface of the semiconductor wafer. The active cell may include at least one insulated-gate bipolar transistor surrounded by the edge termination region in the semiconductor wafer. The termination charge region has a conductivity type opposite of that of the semiconductor wafer. The termination charge region is adjacent to at least one guard ring in the semiconductor wafer.
    Type: Application
    Filed: July 2, 2015
    Publication date: January 21, 2016
    Inventors: Russell Turner, Rajeev Krishna Vytla, Luther-King Ngwendson, Nicholas Limburn
  • Publication number: 20160020279
    Abstract: An edge termination structure is disclosed. The edge termination structure includes an active cell in a semiconductor wafer, an edge termination region adjacent the active cell in the semiconductor wafer, where the edge termination region includes recessed field oxide regions and guard rings adjacent to the active cell. At least one of the guard rings has a depth greater than a depth of at least one of the recessed field oxide regions. A top surface of each of the recessed field oxide regions is substantially coplanar with a top surface of the semiconductor wafer and with a top surface of each of the guard rings. The recessed field oxide regions may be thermally grown in recesses in the semiconductor wafer. The recessed field oxide regions may include silicon dioxide.
    Type: Application
    Filed: July 2, 2015
    Publication date: January 21, 2016
    Inventors: Russell Turner, Rajeev Krishna Vytla, Luther-King Ngwendson, Nicholas Limburn