Patents by Inventor Kouhei Sugihara

Kouhei Sugihara 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: 7183204
    Abstract: A gate insulating film (13) and a gate electrode (14) of non-single crystalline silicon for forming an NMOS transistor are provided on a silicon substrate (10). Using the gate electrode (14) as a mask, n-type dopants having a relatively large mass number (70 or more) such as As ions or Sb ions are implanted, to form a source/drain region of the NMOS transistor, whereby the gate electrode (14) is amorphized. Subsequently, a silicon oxide film (40) is provided to cover the gate electrode (14), at a temperature which is less than the one at which recrystallization of the gate electrode (14) occurs. Thereafter, thermal processing is performed at a temperature of about 1000° C., whereby high compressive residual stress is exerted on the gate electrode (14), and high tensile stress is applied to a channel region under the gate electrode (14). As a result, carrier mobility of the NMOS transistor is enhanced.
    Type: Grant
    Filed: May 12, 2005
    Date of Patent: February 27, 2007
    Assignee: Renesas Technology Corp.
    Inventors: Hirokazu Sayama, Kazunobu Ohta, Hidekazu Oda, Kouhei Sugihara
  • Publication number: 20050202603
    Abstract: A gate insulating film (13) and a gate electrode (14) of non-single crystalline silicon for forming an NMOS transistor are provided on a silicon substrate (10). Using the gate electrode (14) as a mask, n-type dopants having a relatively large mass number (70 or more) such as As ions or Sb ions are implanted, to form a source/drain region of the NMOS transistor, whereby the gate electrode (14) is amorphized. Subsequently, a silicon oxide film (40) is provided to cover the gate electrode (14), at a temperature which is less than the one at which recrystallization of the gate electrode (14) occurs. Thereafter, thermal processing is performed at a temperature of about 1000° C., whereby high compressive residual stress is exerted on the gate electrode (14), and high tensile stress is applied to a channel region under the gate electrode (14). As a result, carrier mobility of the NMOS transistor is enhanced.
    Type: Application
    Filed: May 12, 2005
    Publication date: September 15, 2005
    Applicant: Renesas Technology Corp.
    Inventors: Hirokazu Sayama, Kazunobu Ohta, Hidekazu Oda, Kouhei Sugihara
  • Patent number: 6906393
    Abstract: A gate insulating film (13) and a gate electrode (14) of non-single crystalline silicon for forming an nMOS transistor are provided on a silicon substrate (10). Using the gate electrode (14) as a mask, n-type dopants having a relatively large mass number (70 or more) such as As ions or Sb ions are implanted, to form a source/drain region of the nMOS transistor, whereby the gate electrode (14) is amorphized. Subsequently, a silicon oxide film (40) is provided to cover the gate electrode (14), at a temperature which is less than the one at which recrystallization of the gate electrode (14) occurs. Thereafter, thermal processing is performed at a temperature of about 1000° C., whereby high compressive residual stress is exerted on the gate electrode (14), and high tensile stress is applied to a channel region under the gate electrode (14). As a result, carrier mobility of the nMOS transistor is enhanced.
    Type: Grant
    Filed: July 17, 2003
    Date of Patent: June 14, 2005
    Assignee: Renesas Technology Corp.
    Inventors: Hirokazu Sayama, Kazunobu Ohta, Hidekazu Oda, Kouhei Sugihara
  • Patent number: 6872642
    Abstract: A method of manufacturing a semiconductor device is provided which can suppress leakage current increases by making into silicide. Impurity that suppresses silicide formation reaction (suppression impurity), such as germanium, is introduced into source/drain regions (16, 36) from their upper surfaces. In the source/drain regions (16, 36), a region shallower than a region where the suppression impurity is distributed (50) is made into silicide, so that a silicide film (51) is formed in the source/drain regions (16, 36). Thus, by making the region shallower than the region (50) into silicide, it is possible to suppress that silicide formation reaction extends to the underside of the region to be made into silicide. This enables to reduce the junction leakage between the source/drain regions (16, 36) and a well region.
    Type: Grant
    Filed: May 21, 2003
    Date of Patent: March 29, 2005
    Assignee: Renesas Technology Corp.
    Inventors: Hidekazu Oda, Hirokazu Sayama, Kazunobu Ohta, Kouhei Sugihara
  • Patent number: 6835610
    Abstract: A method of manufacturing a semiconductor device includes forming a gate insulating film on a semiconductor substrate, forming a polysilicon layer on the gate insulating film, implanting ions into the polysilicon layer, patterning the polysilicon layer to form a gate electrode, annealing the gate electrode, and siliciding an upper portion of the gate electrode to form a silicide layer that has a lower portion facing the gate electrode and an upper portion opposite to the lower portion, the upper portion of the silicide layer being wider than the lower portion. A total dose of ions implanted during the step of implanting is 6×1015/cm2 or larger.
    Type: Grant
    Filed: June 3, 2003
    Date of Patent: December 28, 2004
    Assignee: Renesas Technology Corp.
    Inventors: Hirokazu Sayama, Kazunobu Ohta, Hidekazu Oda, Kouhei Sugihara
  • Publication number: 20040101999
    Abstract: A method of manufacturing a semiconductor device is provided which can suppress leakage current increases by making into silicide. Impurity that suppresses silicide formation reaction (suppression impurity), such as germanium, is introduced into source/drain regions (16, 36) from their upper surfaces. In the source/drain regions (16, 36), a region shallower than a region where the suppression impurity is distributed (50) is made into silicide, so that a silicide film (51) is formed in the source/drain regions (16, 36). Thus, by making the region shallower than the region (50) into silicide, it is possible to suppress that silicide formation reaction extends to the underside of the region to be made into silicide. This enables to reduce the junction leakage between the source/drain regions (16, 36) and a well region.
    Type: Application
    Filed: May 21, 2003
    Publication date: May 27, 2004
    Applicant: Renesas Technology Corp.
    Inventors: Hidekazu Oda, Hirokazu Sayama, Kazunobu Ohta, Kouhei Sugihara
  • Publication number: 20040097030
    Abstract: A gate insulating film (13) and a gate electrode (14) of non-single crystalline silicon for forming an nMOS transistor are provided on a silicon substrate (10). Using the gate electrode (14) as a mask, n-type dopants having a relatively large mass number (70 or more) such as As ions or Sb ions are implanted, to form a source/drain region of the nMOS transistor, whereby the gate electrode (14) is amorphized. Subsequently, a silicon oxide film (40) is provided to cover the gate electrode (14), at a temperature which is less than the one at which recrystallization of the gate electrode (14) occurs. Thereafter, thermal processing is performed at a temperature of about 1000° C., whereby high compressive residual stress is exerted on the gate electrode (14), and high tensile stress is applied to a channel region under the gate electrode (14). As a result, carrier mobility of the nMOS transistor is enhanced.
    Type: Application
    Filed: July 17, 2003
    Publication date: May 20, 2004
    Applicant: Renesas Technology Corp.
    Inventors: Hirokazu Sayama, Kazunobu Ohta, Hidekazu Oda, Kouhei Sugihara
  • Publication number: 20040043549
    Abstract: A semiconductor device which provides for reduction of a gate length and a resistance of a gate electrode of a MOS transistor, and a manufacturing method thereof, are provided. In forming a gate electrode (4), ions are implanted at a dose of 6×1015/cm2 or larger and annealing is performed, so that an upper portion of the gate electrode (4) expands. A silicide layer (4b) formed in the upper portion of the gate electrode (4) has a shape with an upper portion thereof being wider than a bottom portion thereof in section taken along a channel length direction. On the other hand, a polysilicon layer 4a has a shape with upper and bottom portions thereof having the substantially same width in section taken along a channel length direction, like the conventional structure. Thus, even when the width of the polysilicon layer (4a) is reduced to reduce a gate length, the width of the silicide layer (4b) is kept larger than the gate length, to prevent agglomeration of silicide in the silicide layer (4b).
    Type: Application
    Filed: June 3, 2003
    Publication date: March 4, 2004
    Applicant: Renesas Technology Corp.
    Inventors: Hirokazu Sayama, Kazunobu Ohta, Hidekazu Oda, Kouhei Sugihara