Patents by Inventor Nathan Kraft

Nathan Kraft 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: 8742401
    Abstract: A field effect transistor includes a plurality of trenches extending into a semiconductor region of a first conductivity type. The plurality of trenches includes a plurality of gated trenches and a plurality of non-gated trenches. A body region of a second conductivity extends in the semiconductor region between adjacent trenches. A dielectric material fills a bottom portion of each of the gated and non-gated trenches. A gate electrode is disposed in each gated trench. A conductive material of the second conductivity type is disposed in each non-gated trench such that the conductive material and contacts corresponding body regions along sidewalls of the non-gated trench.
    Type: Grant
    Filed: October 31, 2013
    Date of Patent: June 3, 2014
    Assignee: Fairchild Semiconductor Corporation
    Inventors: Hamza Yilmaz, Daniel Calafut, Steven Sapp, Nathan Kraft, Ashok Challa
  • Publication number: 20140054691
    Abstract: A field effect transistor includes a plurality of trenches extending into a semiconductor region of a first conductivity type. The plurality of trenches includes a plurality of gated trenches and a plurality of non-gated trenches. A body region of a second conductivity extends in the semiconductor region between adjacent trenches. A dielectric material fills a bottom portion of each of the gated and non-gated trenches. A gate electrode is disposed in each gated trench. A conductive material of the second conductivity type is disposed in each non-gated trench such that the conductive material and contacts corresponding body regions along sidewalls of the non-gated trench.
    Type: Application
    Filed: October 31, 2013
    Publication date: February 27, 2014
    Applicant: Fairchild Semiconductor Corporation
    Inventors: Hamza Yilmaz, Daniel Calafut, Steven Sapp, Nathan Kraft, Ashok Challa
  • Patent number: 8592895
    Abstract: A field effect transistor includes a plurality of trenches extending into a semiconductor region of a first conductivity type. The plurality of trenches includes a plurality of gated trenches and a plurality of non-gated trenches. A body region of a second conductivity extends in the semiconductor region between adjacent trenches. A dielectric material fills a bottom portion of each of the gated and non-gated trenches. A gate electrode is disposed in each gated trench. A conductive material of the second conductivity type is disposed in each non-gated trench such that the conductive material and contacts corresponding body regions along sidewalls of the non-gated trench.
    Type: Grant
    Filed: October 1, 2012
    Date of Patent: November 26, 2013
    Assignee: Fairchild Semiconductor Corporation
    Inventors: Hamza Yilmaz, Daniel Calafut, Steven Sapp, Nathan Kraft, Ashok Challa
  • Patent number: 8278705
    Abstract: A field effect transistor includes a plurality of trenches extending into a semiconductor region of a first conductivity type. The plurality of trenches includes a plurality of gated trenches and a plurality of non-gated trenches. A body region of a second conductivity extends in the semiconductor region between adjacent trenches. A dielectric material fills a bottom portion of each of the gated and non-gated trenches. A gate electrode is disposed in each gated trench. A conductive material of the second conductivity type is disposed in each non-gated trench such that the conductive material and contacts corresponding body regions along sidewalls of the non-gated trench.
    Type: Grant
    Filed: June 2, 2011
    Date of Patent: October 2, 2012
    Assignee: Fairchild Semiconductor Corporation
    Inventor: Nathan Kraft
  • Publication number: 20110303975
    Abstract: A field effect transistor includes a plurality of trenches extending into a semiconductor region of a first conductivity type. The plurality of trenches includes a plurality of gated trenches and a plurality of non-gated trenches. A body region of a second conductivity extends in the semiconductor region between adjacent trenches. A dielectric material fills a bottom portion of each of the gated and non-gated trenches. A gate electrode is disposed in each gated trench. A conductive material of the second conductivity type is disposed in each non-gated trench such that the conductive material and contacts corresponding body regions along sidewalls of the non-gated trench.
    Type: Application
    Filed: June 2, 2011
    Publication date: December 15, 2011
    Inventors: Hamza Yilmaz, Daniel Calafut, Steven Sapp, Nathan Kraft, Ashok Challa
  • Publication number: 20110204436
    Abstract: A field effect transistor (FET) in a semiconductor die including an active region housing active cells, a non-active region with no active cells therein, a drift region of a first conductivity type, a body region of a second conductivity type over the drift region, and a plurality of trenches extending through the body region and into the drift region. Each trench includes a shield electrode and a gate electrode, the shield electrode being disposed below the gate electrode. The FET further includes source regions of the first conductivity type in the body region adjacent to each trench, heavy body regions of the second conductivity type in the body regions adjacent the source regions, and a source interconnect layer contacting the source regions and heavy body regions. The shield electrode and the gate electrode extend out of each trench and into the non-active region where the shield electrode and gate electrode are electrically connected together by a gate interconnect layer.
    Type: Application
    Filed: December 27, 2010
    Publication date: August 25, 2011
    Inventors: Nathan Kraft, Christopher Boguslaw Kocon, Paul Thorup
  • Patent number: 7955920
    Abstract: A field effect transistor includes a plurality of trenches extending into a semiconductor region of a first conductivity type. The plurality of trenches include a plurality of gated trenches and a plurality of non-gated trenches. A body region of a second conductivity extends in the semiconductor region between adjacent trenches. A dielectric material fills a bottom portion of each of the gated and non-gated trenches. A gate electrode is disposed in each gated trench. A conductive material of the second conductivity type is disposed in each non-gated trench such that the conductive material and contacts corresponding body regions along sidewalls of the non-gated trench.
    Type: Grant
    Filed: June 23, 2010
    Date of Patent: June 7, 2011
    Assignee: Fairchild Semiconductor Corporation
    Inventor: Nathan Kraft
  • Patent number: 7859047
    Abstract: A field effect transistor (FET) includes a plurality of trenches extending into a semiconductor region. Each trench includes a gate electrode and a shield electrode with an inter-electrode dielectric therebetween. A body region extends between each pair of adjacent trenches, and source regions extend in each body region adjacent to the trenches. A first interconnect layer contacts the source and body regions. The plurality of trenches extend in an active region of the FET, and the shield electrode and gate electrode extend out of each trench and into a non-active region of the FET where the shield electrodes and gate electrodes are electrically connected together by a second interconnect layer. The electrical connection between the shield and gate electrodes is made through periodic contact openings formed in a gate runner region of the non-active region.
    Type: Grant
    Filed: November 11, 2008
    Date of Patent: December 28, 2010
    Assignee: Fairchild Semiconductor Corporation
    Inventors: Nathan Kraft, Christopher Boguslaw Kocon, Paul Thorup
  • Publication number: 20100258855
    Abstract: A field effect transistor includes a plurality of trenches extending into a semiconductor region of a first conductivity type. The plurality of trenches include a plurality of gated trenches and a plurality of non-gated trenches. A body region of a second conductivity extends in the semiconductor region between adjacent trenches. A dielectric material fills a bottom portion of each of the gated and non-gated trenches. A gate electrode is disposed in each gated trench. A conductive material of the second conductivity type is disposed in each non-gated trench such that the conductive material and contacts corresponding body regions along sidewalls of the non-gated trench.
    Type: Application
    Filed: June 23, 2010
    Publication date: October 14, 2010
    Inventors: Hamza Yilmaz, Daniel Calafut, Steven Sapp, Nathan Kraft, Ashok Challa
  • Patent number: 7767524
    Abstract: A method of forming a charge balance MOSFET includes the following steps. A substrate with an overlying epitaxial layer both of a first conductivity type, are provided. A gate trench extending through the epitaxial layer and terminating within the substrate is formed. A shield dielectric lining sidewalls and bottom surface of the gate trench is formed. A shield electrode is formed in the gate trench. A gate dielectric layer is formed along upper sidewalls of the gate trench. A gate electrode is formed in the gate trench such that the gate electrode extends over but is insulated from the shield electrode. A deep dimple extending through the epitaxial layer and terminating within the substrate is formed such that the deep dimple is laterally spaced from the gate trench. The deep dimple is filled with silicon material of the second conductivity type.
    Type: Grant
    Filed: October 20, 2009
    Date of Patent: August 3, 2010
    Assignee: Fairchild Semiconductor Corporatiion
    Inventors: Hamza Yilmaz, Daniel Calafut, Steven Sapp, Nathan Kraft, Ashok Challa
  • Publication number: 20100038708
    Abstract: A method of forming a charge balance MOSFET includes the following steps. A substrate with an overlying epitaxial layer both of a first conductivity type, are provided. A gate trench extending through the epitaxial layer and terminating within the substrate is formed. A shield dielectric lining sidewalls and bottom surface of the gate trench is formed. A shield electrode is formed in the gate trench. A gate dielectric layer is formed along upper sidewalls of the gate trench. A gate electrode is formed in the gate trench such that the gate electrode extends over but is insulated from the shield electrode. A deep dimple extending through the epitaxial layer and terminating within the substrate is formed such that the deep dimple is laterally spaced from the gate trench. The deep dimple is filled with silicon material of the second conductivity type.
    Type: Application
    Filed: October 20, 2009
    Publication date: February 18, 2010
    Inventors: Hamza Yilmaz, Daniel Calafut, Steven Sapp, Nathan Kraft, Ashok Challa
  • Patent number: 7625799
    Abstract: A semiconductor region with an epitaxial layer extending over the semiconductor region is provided. A first silicon etch is performed to form an upper trench portion extending into and terminating within the epitaxial layer. A protective material is formed extending along sidewalls of the upper trench portion and over mesa regions adjacent the upper trench portion but not along a bottom surface of the upper trench portion. A second silicon etch is performed to form a lower trench portion extending from the bottom surface of the upper trench portion through the epitaxial layer and terminating within the semiconductor region, such that the lower trench portion is narrower than the upper trench portion.
    Type: Grant
    Filed: April 6, 2009
    Date of Patent: December 1, 2009
    Assignee: Fairchild Semiconductor Corporation
    Inventors: Hamza Yilmaz, Daniel Calafut, Steven Sapp, Nathan Kraft, Ashok Challa
  • Publication number: 20090191678
    Abstract: A semiconductor region with an epitaxial layer extending over the semiconductor region is provided. A first silicon etch is performed to form an upper trench portion extending into and terminating within the epitaxial layer. A protective material is formed extending along sidewalls of the upper trench portion and over mesa regions adjacent the upper trench portion but not along a bottom surface of the upper trench portion. A second silicon etch is performed to form a lower trench portion extending from the bottom surface of the upper trench portion through the epitaxial layer and terminating within the semiconductor region, such that the lower trench portion is narrower than the upper trench portion.
    Type: Application
    Filed: April 6, 2009
    Publication date: July 30, 2009
    Inventors: Hamza Yilmaz, Daniel Calafut, Steven Sapp, Nathan Kraft, Ashok Challa
  • Patent number: 7514322
    Abstract: A FET includes a trench in a semiconductor region. The trench has a lower portion with a shield electrode therein, and an upper portion with a gate electrode therein, where the upper portion is wider than the lower portion. The semiconductor region includes a substrate of a first conductivity type and a first silicon region of a second conductivity type over the substrate. The first silicon region has a first portion extending to a depth intermediate top and bottom surfaces of the gate electrode. The first silicon region has a second portion extending to a depth intermediate top and bottom surfaces of the shield electrode. The semiconductor region further includes a second silicon region of the first conductivity type between the lower trench portion and the second portion of the first silicon region that has a laterally-graded doping concentration decreasing in a direction away from the sidewalls of the lower trench portion.
    Type: Grant
    Filed: May 22, 2008
    Date of Patent: April 7, 2009
    Assignee: Fairchild Semiconductor Corporation
    Inventors: Hamza Yilmaz, Daniel Calafut, Steven Sapp, Nathan Kraft, Ashok Challa
  • Publication number: 20090057754
    Abstract: A field effect transistor (FET) includes a plurality of trenches extending into a semiconductor region. Each trench includes a gate electrode and a shield electrode with an inter-electrode dielectric therebetween. A body region extends between each pair of adjacent trenches, and source regions extend in each body region adjacent to the trenches. A first interconnect layer contacts the source and body regions. The plurality of trenches extend in an active region of the FET, and the shield electrode and gate electrode extend out of each trench and into a non-active region of the FET where the shield electrodes and gate electrodes are electrically connected together by a second interconnect layer. The electrical connection between the shield and gate electrodes is made through periodic contact openings formed in a gate runner region of the non-active region.
    Type: Application
    Filed: November 11, 2008
    Publication date: March 5, 2009
    Inventors: Nathan Kraft, Christopher Boguslaw Kocon, Paul Thorup
  • Patent number: 7473603
    Abstract: A method of forming a field effect transistor includes the following steps. A trench is formed in a semiconductor region, and a shield dielectric layer lining lower sidewalls and a bottom surface of the trench is formed. A shield electrode is formed in a lower portion of the trench, and a dielectric layer is formed along upper trench sidewalls and over the shield electrode. A gate electrode is formed in the trench over the shield electrode, and an interconnect layer connecting the gate electrode and the shield electrode is formed.
    Type: Grant
    Filed: November 12, 2007
    Date of Patent: January 6, 2009
    Assignee: Fairchild Semiconductor Corporation
    Inventors: Nathan Kraft, Christopher Boguslaw Kocon, Paul Thorup
  • Publication number: 20080258213
    Abstract: A FET includes a trench in a semiconductor region. The trench has a lower portion with a shield electrode therein, and an upper portion with a gate electrode therein, where the upper portion is wider than the lower portion. The semiconductor region includes a substrate of a first conductivity type and a first silicon region of a second conductivity type over the substrate. The first silicon region has a first portion extending to a depth intermediate top and bottom surfaces of the gate electrode. The first silicon region has a second portion extending to a depth intermediate top and bottom surfaces of the shield electrode. The semiconductor region further includes a second silicon region of the first conductivity type between the lower trench portion and the second portion of the first silicon region that has a laterally-graded doping concentration decreasing in a direction away from the sidewalls of the lower trench portion.
    Type: Application
    Filed: May 22, 2008
    Publication date: October 23, 2008
    Inventors: Hamza Yilmaz, Daniel Calafut, Steven Sapp, Nathan Kraft, Ashok Challa
  • Patent number: 7393749
    Abstract: A field effect transistor is formed as follows. A semiconductor region of a first conductivity type with an epitaxial layer of a second conductivity extending over the semiconductor region is provided. A trench extending through the epitaxial layer and terminating in the semiconductor region is formed. A two-pass angled implant of dopants of the first conductivity type is carried out to thereby form a region of first conductivity type along the trench sidewalls. A threshold voltage adjust implant of dopants of the second conductivity type is carried out to thereby convert a conductivity type of a portion of the region of first conductivity type extending along upper sidewalls of the trench to the second conductivity type. Source regions of the first conductivity type flanking each side of the trench are formed.
    Type: Grant
    Filed: June 8, 2006
    Date of Patent: July 1, 2008
    Assignee: Fairchild Semiconductor Corporation
    Inventors: Hamza Yilmaz, Daniel Calafut, Steven Sapp, Nathan Kraft, Ashok Challa
  • Publication number: 20080064168
    Abstract: A method of forming a field effect transistor includes the following steps. A trench is formed in a semiconductor region, and a shield dielectric layer lining lower sidewalls and a bottom surface of the trench is formed. A shield electrode is formed in a lower portion of the trench, and a dielectric layer is formed along upper trench sidewalls and over the shield electrode. A gate electrode is formed in the trench over the shield electrode, and an interconnect layer connecting the gate electrode and the shield electrode is formed.
    Type: Application
    Filed: November 12, 2007
    Publication date: March 13, 2008
    Inventors: Nathan Kraft, Christopher Kocon, Paul Thorup
  • Patent number: 7319256
    Abstract: A field effect transistor (FET) includes a plurality of trenches extending into a semiconductor region. Each trench includes a gate electrode and a shield electrode with an inter-electrode dielectric therebetween. The trench extends in an active region of the FET, and the shield electrode and gate electrode extend out of the trench and into a non-active region of the FET where the shield electrode and gate electrode are electrically connected together by a first interconnect layer.
    Type: Grant
    Filed: June 19, 2006
    Date of Patent: January 15, 2008
    Assignee: Fairchild Semiconductor Corporation
    Inventors: Nathan Kraft, Christopher Boguslaw Kocon, Paul Thorup