Patents by Inventor Hiroki Shirai

Hiroki Shirai 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).

  • Publication number: 20110284991
    Abstract: A semiconductor device has a substrate; a multi-layered interconnect formed on the substrate, and having a plurality of interconnect layers, each of which being configured by an interconnect and an insulating layer, stacked therein; a memory circuit formed in a memory circuit region on the substrate in a plan view, and having a peripheral circuit and at least one capacitor element embedded in the multi-layered interconnect; and a logic circuit formed in a logic circuit region on the substrate, wherein the capacitor element is configured by a lower electrode, a capacitor insulating film, an upper electrode, an embedded electrode and an upper interconnect; the top surface of the upper interconnect, and the top surface of the interconnect configuring the logic circuit formed in the same interconnect layer with the upper interconnect, are aligned to the same plane.
    Type: Application
    Filed: May 12, 2011
    Publication date: November 24, 2011
    Inventors: Kenichiro HIJIOKA, Ippei Kume, Naoya Inoue, Hiroki Shirai, Jun Kawahara, Yoshihiro Hayashi
  • Publication number: 20110156164
    Abstract: A semiconductor device having a DRAM region and a logic region embedded together therein, including a first transistor formed in a DRAM region, and having a first source/drain region containing at least a first impurity, and a second transistor formed in a logic region, and having a second source/drain region containing at least a second impurity, wherein each of the first source/drain region and the second source/drain region has a silicide layer respectively formed in the surficial portion thereof, and the first source/drain region has a junction depth which is determined by an impurity and is deeper than the junction depth of the second source/drain region.
    Type: Application
    Filed: February 11, 2011
    Publication date: June 30, 2011
    Applicant: RENESAS ELECTRONICS CORPORATION
    Inventor: Hiroki Shirai
  • Patent number: 7911005
    Abstract: A semiconductor device having a DRAM region and a logic region embedded together therein, including a first transistor formed in a DRAM region, and having a first source/drain region containing arsenic and phosphorus as impurities; and a second transistor formed in a logic region, and having a second source/drain region containing at least arsenic as an impurity, wherein each of the first source/drain region and the second source/drain region has a silicide layer respectively formed in the surficial portion thereof, and the first source/drain region has a junction depth which is determined by phosphorus and is deeper than the junction depth of the second source/drain region.
    Type: Grant
    Filed: July 17, 2009
    Date of Patent: March 22, 2011
    Assignee: RENESAS Electronics Corporation
    Inventor: Hiroki Shirai
  • Publication number: 20100078734
    Abstract: A first transistor and a second transistor are formed in a first element formation region, and a third transistor is formed in a second element formation region. The three transistors are of the same conductive type, and the first transistor and the second transistor have the same threshold voltage. A first well is formed in the first element formation region by use of a first mask pattern, and a second well is formed in the second element formation region by use of a second mask pattern. A channel region of the first transistor and a channel region of the second transistor have a shape which is line-symmetrical with respect to a reference line. The first mask pattern has a shape which is line-symmetrical with respect to the reference line.
    Type: Application
    Filed: September 14, 2009
    Publication date: April 1, 2010
    Applicant: NEC ELECTRONICS CORPORATION
    Inventors: TAKASHI SAKOH, HIROKI SHIRAI
  • Publication number: 20100013027
    Abstract: A semiconductor device having a DRAM region and a logic region embedded together therein, including a first transistor formed in a DRAM region, and having a first source/drain region containing arsenic and phosphorus as impurities; and a second transistor formed in a logic region, and having a second source/drain region containing at least arsenic as an impurity, wherein each of the first source/drain region and the second source/drain region has a silicide layer respectively formed in the surficial portion thereof, and the first source/drain region has a junction depth which is determined by phosphorus and is deeper than the junction depth of the second source/drain region.
    Type: Application
    Filed: July 17, 2009
    Publication date: January 21, 2010
    Applicant: NEC ELECTRONICS CORPORATION
    Inventor: Hiroki Shirai
  • Patent number: 7645692
    Abstract: In one embodiment of the present invention, provided is a semiconductor device having a silicon substrate provided with a DRAM region containing first transistors and capacitor elements, and with a logic region containing second transistors. A minimum gate length of the second transistors provided in the logic region is smaller than a minimum gate length of the first transistors provided in the DRAM region. One of a cobalt silicide layer and a titanium silicide layer is provided on source/drain regions and on gate electrodes of the first transistors provided in the DRAM region, and a nickel-containing silicide layer is provided on source/drain regions and on gate electrodes of the second transistors provided in the logic region.
    Type: Grant
    Filed: November 27, 2007
    Date of Patent: January 12, 2010
    Assignee: NEC Electronics Corporation
    Inventors: Yoshihisa Matsubara, Hiroki Shirai
  • Publication number: 20080121964
    Abstract: In one embodiment of the present invention, provided is a semiconductor device having a silicon substrate provided with a DRAM region containing first transistors and capacitor elements, and with a logic region containing second transistors. A minimum gate length of the second transistors provided in the logic region is smaller than a minimum gate length of the first transistors provided in the DRAM region. One of a cobalt silicide layer and a titanium silicide layer is provided on source/drain regions and on gate electrodes of the first transistors provided in the DRAM region, and a nickel-containing silicide layer is provided on source/drain regions and on gate electrodes of the second transistors provided in the logic region.
    Type: Application
    Filed: November 27, 2007
    Publication date: May 29, 2008
    Applicant: NEC Electronics Corporation
    Inventors: Yoshihisa MATSUBARA, Hiroki SHIRAI
  • Publication number: 20030030145
    Abstract: The present invention provides a method of forming a gate structure of a floating gate MOS field effect transistor.
    Type: Application
    Filed: September 27, 2002
    Publication date: February 13, 2003
    Applicant: NEC CORPORATION
    Inventor: Hiroki Shirai
  • Patent number: 6482697
    Abstract: The present invention provides a method of forming a gate structure of a floating gate MOS field effect transistor.
    Type: Grant
    Filed: November 6, 2000
    Date of Patent: November 19, 2002
    Assignee: NEC Corporation
    Inventor: Hiroki Shirai
  • Patent number: 5972750
    Abstract: There are disclosed a nonvolatile semiconductor memory device, which is capable of maintaining a high capacitance ratio even when a memory cell is formed in a micronized size without increasing the number of manufacturing steps, and its manufacturing method. In a flash memory having buried diffusion layer type cells, a source region and drain regions and are formed in self alignment with a polycrystalline film pattern which has a polycrystalline silicon film having projecting and recessing parts in its upper surface.
    Type: Grant
    Filed: February 2, 1998
    Date of Patent: October 26, 1999
    Assignee: NEC Corporation
    Inventors: Hiroki Shirai, Taishi Kubota, Ichiro Honma, Hirohito Watanabe, Haruhiko Ono, Takeshi Okazawa
  • Patent number: 5973355
    Abstract: There is disclosed a nonvolatile semiconductor memory device, which is capable of maintaining a high capacitance ratio even when a memory cell is formed in a micronized size without increasing the number of manufacturing steps. In a flash memory having buried diffusion layer type cells, a source region and drain regions and are formed in self alignment with a polycrystalline film pattern which has a polycrystalline silicon film having projecting and recessing parts in its upper surface.
    Type: Grant
    Filed: May 5, 1997
    Date of Patent: October 26, 1999
    Assignee: NEC Corporation
    Inventors: Hiroki Shirai, Taishi Kubota, Ichiro Honma, Hirohito Watanabe, Haruhiko Ono, Takeshi Okazawa
  • Patent number: 5737264
    Abstract: A non-volatile semiconductor memory cell comprises a source region having an N.sup.+ type diffusion layer, an N.sup.- diffusion layer, and N type diffusion layer, the N.sup.- type diffusion layer being formed by injecting phosphorus ions by an inclined rotating ion injecting method. The overlap width of the N.sup.- type diffusion layer and the floating gate electrode is larger than the overlap width of the N.sup.+ type diffusion layer and the floating gate electrode, and the junction depth of the N type diffusion layer is larger than the junction depth of the N.sup.+ type diffusion layer. Thus, in flash memory having memory cells according to the present invention, even if the size of the memory cells is reduced, erase time can be shortened without sacrificing erase function and performance.
    Type: Grant
    Filed: March 25, 1996
    Date of Patent: April 7, 1998
    Assignee: NEC Corporation
    Inventor: Hiroki Shirai
  • Patent number: 5541877
    Abstract: Disclosed is an electrically erasable nonvolatile semiconductor memory device having a floating gate electrode formed on a semiconductor substrate through a first gate insulating film, a control gate electrode formed on the floating gate electrode through a second gate insulating film, and source and drain regions spaced apart from each other under the floating gate electrode so as to partially overlap the floating gate electrode, wherein an electric field buffering means for relaxing an electric field generated between a peripheral portion of an element isolation region and an end portion of the floating gate electrode in application of an erase voltage is selectively formed as a lightly doped region in a source region surface portion of the peripheral portion of the element isolation region.
    Type: Grant
    Filed: September 7, 1995
    Date of Patent: July 30, 1996
    Assignee: NEC Corporation
    Inventor: Hiroki Shirai
  • Patent number: 5295107
    Abstract: A method of controlling the nonvolatile memory device comprising making over-erasing simultaneously a set of EEPROM elements and then setting simultaneously the threshold voltages of said set of EEPROM elements back to the specified threshold-voltage values. The over-erasing is accomplished by applying a first pulse between the source and the control gate to induce the first FN current across the gate insulating film. The setting-back is accomplished by applying a second pulse between the well and the control gate to induce the second FN current flowing reversely to the first FN current.
    Type: Grant
    Filed: March 1, 1993
    Date of Patent: March 15, 1994
    Assignee: NEC Corporation
    Inventors: Takeshi Okazawa, Ken-Ichi Oyama, Hiroki Shirai