Patents by Inventor Yoshiya Kawashima

Yoshiya Kawashima 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: 8643103
    Abstract: A semiconductor device for preventing an outer well from being separated by a trench gate electrode from the well of a cell region while suppressing increase in the gate resistance in which buried gate electrodes extending in a direction overlapping a gate contact region extend only before a gate electrode so as not to overlap the gate electrode, the source contact situated between each of the buried gate electrodes is shorter than the buried gate electrode in the vertical direction, the ends of the buried gate electrodes on the side of the gate electrode are connected with each other by a buried connecting electrode disposed before the gate electrode, the buried connecting electrode extends in a direction parallel with the longer side of the semiconductor device, and is not connected to the buried gate electrode on the side of the contact situated adjacent to the contact-side buried gate electrode.
    Type: Grant
    Filed: September 24, 2011
    Date of Patent: February 4, 2014
    Assignee: Renesas Electronics Corporation
    Inventor: Yoshiya Kawashima
  • Patent number: 8536647
    Abstract: A semiconductor device of the present invention has a first-conductivity-type substrate having second-conductivity-type base regions exposed to a first surface thereof; trench gates provided to a first surface of the substrate; first-conductivity-type source regions formed shallower than the base regions; a plurality of second-conductivity-type column regions located between two adjacent trench gates in a plan view, while being spaced from each other in a second direction normal to the first direction; the center of each column region and the center of each base contact region fall on the center line between two trench gates; and has no column region formed below the trench gates.
    Type: Grant
    Filed: July 11, 2011
    Date of Patent: September 17, 2013
    Assignee: Renesas Electronics Corporation
    Inventor: Yoshiya Kawashima
  • Publication number: 20120098060
    Abstract: A semiconductor device for preventing an outer well from being separated by a trench gate electrode from the well of a cell region while suppressing increase in the gate resistance in which buried gate electrodes extending in a direction overlapping a gate contact region extend only before a gate electrode so as not to overlap the gate electrode, the source contact situated between each of the buried gate electrodes is shorter than the buried gate electrode in the vertical direction, the ends of the buried gate electrodes on the side of the gate electrode are connected with each other by a buried connecting electrode disposed before the gate electrode, the buried connecting electrode extends in a direction parallel with the longer side of the semiconductor device, and is not connected to the buried gate electrode on the side of the contact situated adjacent to the contact-side buried gate electrode.
    Type: Application
    Filed: September 24, 2011
    Publication date: April 26, 2012
    Applicant: RENESAS ELECTRONICS CORPORATION
    Inventor: Yoshiya Kawashima
  • Publication number: 20110266618
    Abstract: A semiconductor device of the present invention has a first-conductivity-type substrate having second-conductivity-type base regions exposed to a first surface thereof; trench gates provided to a first surface of the substrate; first-conductivity-type source regions formed shallower than the base regions; a plurality of second-conductivity-type column regions located between two adjacent trench gates in a plan view, while being spaced from each other in a second direction normal to the first direction; the center of each column region and the center of each base contact region fall on the center line between two trench gates; and has no column region formed below the trench gates.
    Type: Application
    Filed: July 11, 2011
    Publication date: November 3, 2011
    Applicant: RENESAS ELECTRONICS CORPORATION
    Inventor: Yoshiya KAWASHIMA
  • Patent number: 8008717
    Abstract: A semiconductor device of the present invention has a first-conductivity-type substrate having second-conductivity-type base regions exposed to a first surface thereof; trench gates provided to a first surface of the substrate; first-conductivity-type source regions formed shallower than the base regions; a plurality of second-conductivity-type column regions located between two adjacent trench gates in a plan view, while being spaced from each other in a second direction normal to the first direction; the center of each column region and the center of each base contact region fall on the center line between two trench gates; and has no column region formed below the trench gates.
    Type: Grant
    Filed: July 7, 2009
    Date of Patent: August 30, 2011
    Assignee: Renesas Electronics Corporation
    Inventor: Yoshiya Kawashima
  • Patent number: 7829417
    Abstract: A semiconductor apparatus with a superjunction structure includes a gate electrode which fills a trench that is formed in an epitaxial layer, and a column region which is surrounded by the gate electrode in a plane view. A photomask for forming the column region is elaborated. The photomask has a compensation pattern that compensates a deformation of a photo resist pattern caused by photo interference and a deformation of the ion implantation region diffused by heat treatment. Therefore extending direction of the gate electrode and the outer edge of the column region are substantially parallel.
    Type: Grant
    Filed: May 29, 2008
    Date of Patent: November 9, 2010
    Assignee: NEC Electronics Corporation
    Inventors: Hitoshi Ninomiya, Yoshinao Miura, Yoshiya Kawashima
  • Publication number: 20100025760
    Abstract: A semiconductor device includes a MOSFET cell having a super junction structure and a diode cell connected in parallel with the MOSFET cell and having the same plan shape as the MOSFET cell. The MOSFET cell includes an epitaxial layer of a first conductivity type formed on a semiconductor substrate, a gate electrode and a first column region of a second conductivity type formed in the epitaxial layer, a first base region of the second conductivity type formed on a surface of the epitaxial layer, and a source region of the first conductivity type formed on a surface of the first base region. The diode cell includes a second column region of the second conductivity type formed in the epitaxial layer and having a larger width than the first column region, and a second base region of the second conductivity type formed on the surface of the epitaxial layer.
    Type: Application
    Filed: July 9, 2009
    Publication date: February 4, 2010
    Applicant: NEC Electronics Corporation
    Inventor: Yoshiya KAWASHIMA
  • Patent number: 7649223
    Abstract: An n-type drift region includes an active element region and a peripheral region. A p-type base region is formed at least in the active element region. A trench-type gate electrode is formed in each of the active element region and the peripheral region. An n-type source region formed in the base region. A plurality of p-type column regions is selectively formed separately from one another in each of the active element region and the peripheral region. In a peripheral region, a p-type guard region is formed below the gate electrode. In the active element region, the p-type guard region is not formed below the gate electrode. As a result, it is possible to hold the breakdown voltage in the peripheral region at a higher level than in the active element region while maintaining the low ON resistance due to a superjunction structure and to raise the breakdown voltage performance of the semiconductor device.
    Type: Grant
    Filed: June 28, 2007
    Date of Patent: January 19, 2010
    Assignee: NEC Electronics Corporation
    Inventor: Yoshiya Kawashima
  • Publication number: 20100001341
    Abstract: A semiconductor device of the present invention has a first-conductivity-type substrate having second-conductivity-type base regions exposed to a first surface thereof; trench gates provided to a first surface of the substrate; first-conductivity-type source regions formed shallower than the base regions; a plurality of second-conductivity-type column regions located between two adjacent trench gates in a plan view, while being spaced from each other in a second direction normal to the first direction; the center of each column region and the center of each base contact region fall on the center line between two trench gates; and has no column region formed below the trench gates.
    Type: Application
    Filed: July 7, 2009
    Publication date: January 7, 2010
    Applicant: NEC Electronics Corporation
    Inventor: Yoshiya KAWASHIMA
  • Publication number: 20080299726
    Abstract: A semiconductor apparatus with a superjunction structure includes a gate electrode which fills a trench that is formed in an epitaxial layer, and a column region which is surrounded by the gate electrode in a plane view. A photomask for forming the column region is elaborated. The photomask has a compensation pattern that compensates a deformation of a photo resist pattern caused by photo interference and a deformation of the ion implantation region diffused by heat treatment. Therefore extending direction of the gate electrode and the outer edge of the column region are substantially parallel.
    Type: Application
    Filed: May 29, 2008
    Publication date: December 4, 2008
    Applicant: NEC ELECTRONICS CORPORATION
    Inventors: Hitoshi NINOMIYA, Yoshinao MIURA, Yoshiya KAWASHIMA
  • Publication number: 20080197381
    Abstract: A semiconductor device is provided with a vertical MOSFET including an N-type drift region that has a {110} crystal plane serving as the main surface thereof, a trench gate structure formed in a trench that has a {100} crystal plane serving as a sidewall surface thereof, and plural P-type column region structures provided in the N-type drift region 3, making up the super-junction structure. The P-type column region structures are disposed so as to be separated from each other in a plan view, and each of the plurality of column structures includes a plurality of column regions of the second conductivity type separated from each other in a cross-sectional view. By applying ion implantation of a P-type dopant to the main surface from a direction vertical to the main surface, the P-type column regions are formed down to sufficiently deeper positions in the drift region due to channeling. By so doing, it is possible to obtain a semiconductor device with an enhanced breakdown voltage.
    Type: Application
    Filed: February 12, 2008
    Publication date: August 21, 2008
    Applicant: NEC ELECTRONICS CORPORATION
    Inventors: Yoshiya Kawashima, Yoshinao Miura, Hitoshi Ninomiya
  • Publication number: 20080001217
    Abstract: An n-type drift region includes an active element region and a peripheral region. A p-type base region is formed at least in the active element region. A trench-type gate electrode is formed in each of the active element region and the peripheral region. An n-type source region formed in the base region. A plurality of p-type column regions is selectively formed separately from one another in each of the active element region and the peripheral region. In a peripheral region, a p-type guard region is formed below the gate electrode. In the active element region, the p-type guard region is not formed below the gate electrode. As a result, it is possible to hold the breakdown voltage in the peripheral region at a higher level than in the active element region while maintaining the low ON resistance due to a superjunction structure and to raise the breakdown voltage performance of the semiconductor device.
    Type: Application
    Filed: June 28, 2007
    Publication date: January 3, 2008
    Applicant: NEC ELECTRONICS CORPORATION
    Inventor: Yoshiya Kawashima