Patents by Inventor Allen Hefner

Allen Hefner 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).

  • Power switching semiconductor devices including rectifying junction-shunts
    Patent number: 8546874
    Abstract: A semiconductor device includes a drift layer and a body region that forms a p-n junction with the drift layer. A contactor region is in the body region, and a shunt channel region extends through the body region from the contactor region to the drift layer. The shunt channel region has a length, thickness and doping concentration selected such that: 1) the shunt channel region is fully depleted when zero voltage is applied across the first and second terminals, 2) the shunt channel becomes conductive at a voltages less than the built-in potential of the drift layer to body region p-n junction, and/or 3) the shunt channel is not conductive for voltages that reverse bias the p-n junction between the drift region and the body region.
    Type: Grant
    Filed: October 7, 2011
    Date of Patent: October 1, 2013
    Assignee: Cree, Inc.
    Inventors: Allen Hefner, Sei-Hyung Ryu, Anant Agarwal
  • Power Switching Semiconductor Devices Including Rectifying Junction-Shunts
    Publication number: 20120068263
    Abstract: A semiconductor device includes a drift layer and a body region that forms a p-n junction with the drift layer. A contactor region is in the body region, and a shunt channel region extends through the body region from the contactor region to the drift layer. The shunt channel region has a length, thickness and doping concentration selected such that: 1) the shunt channel region is fully depleted when zero voltage is applied across the first and second terminals, 2) the shunt channel becomes conductive at a voltages less than the built-in potential of the drift layer to body region p-n junction, and/or 3) the shunt channel is not conductive for voltages that reverse bias the p-n junction between the drift region and the body region.
    Type: Application
    Filed: October 7, 2011
    Publication date: March 22, 2012
    Inventors: Allen Hefner, Sei-Hyung Ryu, Anant Agarwal
  • Methods of forming power switching semiconductor devices including rectifying junction-shunts
    Patent number: 8034688
    Abstract: A semiconductor device includes a drift layer having a first conductivity type and a body region adjacent the drift layer. The body region has a second conductivity type opposite the first conductivity type and forms a p-n junction with the drift layer. The device further includes a contactor region in the body region and having the first conductivity type, and a shunt channel region extending through the body region from the contactor region to the drift layer. The shunt channel region has the first conductivity type. The device further includes a first terminal in electrical contact with the body region and the contactor region, and a second terminal in electrical contact with the drift layer.
    Type: Grant
    Filed: September 16, 2009
    Date of Patent: October 11, 2011
    Assignee: Cree, Inc.
    Inventors: Allen Hefner, Sei-Hyung Ryu, Anant Agarwal
  • Power Switching Semiconductor Devices Including Rectifying Junction-Shunts
    Publication number: 20100090271
    Abstract: A semiconductor device includes a drift layer having a first conductivity type and a body region adjacent the drift layer. The body region has a second conductivity type opposite the first conductivity type and forms a p-n junction with the drift layer. The device further includes a contactor region in the body region and having the first conductivity type, and a shunt channel region extending through the body region from the contactor region to the drift layer. The shunt channel region has the first conductivity type. The device further includes a first terminal in electrical contact with the body region and the contactor region, and a second terminal in electrical contact with the drift layer.
    Type: Application
    Filed: September 16, 2009
    Publication date: April 15, 2010
    Inventors: Allen Hefner, Sei-Hyung Ryu, Anant Agarwal
  • Power switching semiconductor devices including rectifying junction-shunts
    Patent number: 7598567
    Abstract: A semiconductor device includes a drift layer having a first conductivity type and a body region adjacent the drift layer. The body region has a second conductivity type opposite the first conductivity type and forms a p-n junction with the drift layer. The device further includes a contactor region in the body region and having the first conductivity type, and a shunt channel region extending through the body region from the contactor region to the drift layer. The shunt channel region has the first conductivity type. The device further includes a first terminal in electrical contact with the body region and the contactor region, and a second terminal in electrical contact with the drift layer.
    Type: Grant
    Filed: November 3, 2006
    Date of Patent: October 6, 2009
    Assignee: Cree, Inc.
    Inventors: Allen Hefner, Sei-Hyung Ryu, Anant Agarwal
  • POWER SWITCHING SEMICONDUCTOR DEVICES INCLUDING RECTIFYING JUNCTION-SHUNTS
    Publication number: 20080121993
    Abstract: A semiconductor device includes a drift layer having a first conductivity type and a body region adjacent the drift layer. The body region has a second conductivity type opposite the first conductivity type and forms a p-n junction with the drift layer. The device further includes a contactor region in the body region and having the first conductivity type, and a shunt channel region extending through the body region from the contactor region to the drift layer. The shunt channel region has the first conductivity type. The device further includes a first terminal in electrical contact with the body region and the contactor region, and a second terminal in electrical contact with the drift layer.
    Type: Application
    Filed: November 3, 2006
    Publication date: May 29, 2008
    Inventors: Allen Hefner, Sei-Hyung Ryu, Anant Agarwal