Patents by Inventor Keiji Ikeda

Keiji Ikeda 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: 20120164800
    Abstract: According to one embodiment, a method of manufacturing a semiconductor device which includes a MISFET, includes: forming a gate insulating film on a semiconductor substrate; forming a gate electrode on the gate insulating film; implanting nitrogen equal to or more than 5.0e14 atoms/cm2 and equal to or less than 1.5e15 atoms/cm2 in the semiconductor substrate by tilted ion implantation in a direction from an outside to an inside with respect to side surfaces of the gate electrode; depositing a metal film including nickel on areas in which nitrogen atoms are implanted, the areas are in a semiconductor substrate on both sides of the gate electrode; and performing first heat processing of reacting the metal film and the semiconductor substrate and forming metal semiconductor compound layers, the shapes of the layers are controlled by the nitrogen profiles of the areas.
    Type: Application
    Filed: December 23, 2011
    Publication date: June 28, 2012
    Inventor: Keiji IKEDA
  • Patent number: 8187957
    Abstract: A field-effect transistor that increases the operation speeds of complementary field-effect transistors. Each of an nMOSFET and a pMODFET has a Ge channel and source and drain regions formed of an NiGe layer. The height of Schottky barriers formed at a junction between a channel region and the source region of the nMOSFET and at a junction between the channel region and the drain region of the nMOSFET is changed by very thin high-concentration segregation layers formed by making As atoms, Sb atoms, S atoms or the like segregate at the time of forming the NiGe layer. As a result, Schottky barrier height suitable for the nMOSFET and the pMODFET can be obtained, this being capable of realizing high-speed CMOSFETS.
    Type: Grant
    Filed: November 1, 2010
    Date of Patent: May 29, 2012
    Assignee: Fujitsu Semiconductor Limited
    Inventor: Keiji Ikeda
  • Publication number: 20110210375
    Abstract: According to one embodiment, a semiconductor device including a tunnel FET, includes a gate electrode, which is formed on a first semiconductor layer formed of Si1-XGeX (0<x?1) through a gate insulating film, a source electrode, which is formed of a compound of a second semiconductor formed mainly using Ge and a metal, a drain electrode, which is formed of a compound of the first semiconductor layer and the metal, and a silicon (Si) thin film, which is formed between the source electrode and the first semiconductor layer. An edge portion of the source electrode and an edge portion of the drain electrode have a positional relationship of Asymmetrical to the gate electrode. The edge portion of the drain electrode is far away from an edge portion of the gate electrode toward a gate external direction compared with the edge portion of the source electrode.
    Type: Application
    Filed: September 23, 2010
    Publication date: September 1, 2011
    Inventors: Keiji IKEDA, Tsutomu Tezuka
  • Publication number: 20110180847
    Abstract: According to one embodiment, a semiconductor device having a Ge- or SiGe-fin structure includes a convex-shaped active area formed along one direction on the surface region of a Si substrate, a buffer layer of Si1-xGex (0<x<1) formed on the active area, and a fin structure of Si1-yGey (x<y?1) formed on the buffer layer. The fin structure has a side surface of a (110) plane perpendicular to the surface of the Si substrate and the width thereof in a direction perpendicular to the one direction of the fin structure is narrower than that of the buffer layer.
    Type: Application
    Filed: September 23, 2010
    Publication date: July 28, 2011
    Inventors: Keiji Ikeda, Tsutomu Tezuka, Yoshihiko Moriyama
  • Publication number: 20110045663
    Abstract: A field-effect transistor that increases the operation speeds of complementary field-effect transistors. Each of an nMOSFET and a pMODFET has a Ge channel and source and drain regions formed of an NiGe layer. The height of Schottky barriers formed at a junction between a channel region and the source region of the nMOSFET and at a junction between the channel region and the drain region of the nMOSFET is changed by very thin high-concentration segregation layers formed by making As atoms, Sb atoms, S atoms or the like segregate at the time of forming the NiGe layer. As a result, Schottky barrier height suitable for the nMOSFET and the pMODFET can be obtained, this being capable of realizing high-speed CMOSFETS.
    Type: Application
    Filed: November 1, 2010
    Publication date: February 24, 2011
    Applicant: FUJITSU SEMICONDUCTOR
    Inventor: Keiji IKEDA
  • Patent number: 7825493
    Abstract: A field-effect transistor that increases the operation speeds of complementary field-effect transistors. Each of an nMOSFET and a pMODFET has a Ge channel and source and drain regions formed of an NiGe layer. The height of Schottky barriers formed at a junction between a channel region and the source region of the nMOSFET and at a junction between the channel region and the drain region of the nMOSFET is changed by very thin high-concentration segregation layers formed by making As atoms, Sb atoms, S atoms, or the like segregate at the time of forming the NiGe layer. As a result, Schottky barrier height suitable for the nMOSFET and the pMODFET can be obtained, thus being capable of realizing high-speed CMOSFETs.
    Type: Grant
    Filed: May 2, 2006
    Date of Patent: November 2, 2010
    Assignee: Fujitsu Semiconductor Limited
    Inventor: Keiji Ikeda
  • Publication number: 20100163150
    Abstract: A rubber composition for a tire includes a rubber component containing at least one of a natural rubber and an epoxidized natural rubber, silica and a natural based wax, wherein the silica is contained in an amount of 10 parts by mass or more based on 100 parts by mass of the rubber component and the natural based wax is contained in an amount of 1.2% by mass or more and 2% by mass or less based on the total mass of the rubber composition for a tire, and to a tread, a side wall, a clinch and a tire using the rubber composition.
    Type: Application
    Filed: March 14, 2008
    Publication date: July 1, 2010
    Inventors: Tomoaki Hirayama, Takao Wada, Noboru Wakabayashi, Keiji Ikeda
  • Publication number: 20100132863
    Abstract: The present invention provides a rubber composition that is used for forming a ply having superior processability upon preparation thereof, with a reduced hysteresis loss, a clinch that is capable of achieving both of good physical characteristics, such as rigidity, hardness and mechanical strength, and improvements in processability and a tread that has high rigidity with a small hysteresis loss and is superior in processability upon preparation thereof, while reducing the amount of use of materials derived from petroleum resources, and a pneumatic tire provided with these. The ply, the clinch apex and the tread are made from a rubber composition that has 100 parts by mass of a rubber component composed of a natural rubber and/or a modified natural rubber, and 25 to 80 parts by mass of silica having a BET specific surface area of not more than 150 m2/g, and the pneumatic tire is provided with these.
    Type: Application
    Filed: February 27, 2008
    Publication date: June 3, 2010
    Inventors: Takashi Miki, Keiji Ikeda
  • Publication number: 20100025744
    Abstract: A semiconductor device includes a gate electrode over a semiconductor substrate, a channel region provided in the semiconductor substrate below the gate electrode, and a strain generation layer configured to apply stress to the channel region, the strain generation layer being configured to apply greater stress in absolute value to the source edge of the channel region than to the drain edge of the channel region.
    Type: Application
    Filed: September 17, 2009
    Publication date: February 4, 2010
    Applicant: FUJITSU MICROELECTRONICS LIMITED
    Inventors: Toshihiko Miyashita, Keiji Ikeda
  • Patent number: 7655516
    Abstract: In an nMOSFET, a gate electrode is formed by a silicide layer comprised of NiSi. In a surface layer of a Ge substrate on both sides of the gate electrode, NiGe layers which are germanide layers comprised of NiGe are formed. On junction interfaces between the NiGe layers and the Ge substrate, first layers are formed which are formed by segregating a predetermined atom with high concentration, and on an interface between the gate electrode and an insulation film, a second layer is formed which is formed by segregating the same atom as that of the first layer with high concentration.
    Type: Grant
    Filed: April 26, 2007
    Date of Patent: February 2, 2010
    Assignee: Fujitsu Microelectronics Limited
    Inventor: Keiji Ikeda
  • Publication number: 20080142855
    Abstract: A MOS transistor includes a silicon substrate, a gate insulating film disposed on the silicon substrate, a gate electrode disposed on the gate insulating film, source/drain regions disposed at both sides of the gate electrode, and a stress-generating region containing a stress-generating substance. The stress-generating region is disposed within the silicon substrate away from a surface of the silicon substrate, between the source/drain regions, and under the gate electrode.
    Type: Application
    Filed: December 18, 2007
    Publication date: June 19, 2008
    Applicant: FUJITSU LIMITED
    Inventors: Keiji IKEDA, Toshihiko MIYASHITA
  • Publication number: 20080064156
    Abstract: In an nMOSFET, a gate electrode is formed by a silicide layer comprised of NiSi. In a surface layer of a Ge substrate on both sides of the gate electrode, NiGe layers which are germanide layers comprised of NiGe are formed. On junction interfaces between the NiGe layers and the Ge substrate, first layers are formed which are formed by segregating a predetermined atom with high concentration, and on an interface between the gate electrode and an insulation film, a second layer is formed which is formed by segregating the same atom as that of the first layer with high concentration.
    Type: Application
    Filed: April 26, 2007
    Publication date: March 13, 2008
    Applicant: FUJITSU LIMITED
    Inventor: Keiji Ikeda
  • Patent number: 7316959
    Abstract: The semiconductor device comprises a semiconductor layer 18 formed on an insulation layer 16, a gate electrode 22 formed on the semiconductor layer with a gate insulation film 20 formed therebetween, a source/drain region 24 formed on the semiconductor layer on both sides of the gate electrode, and a semiconductor region 14 buried in the insulation layer 16 in a region below the gate electrode. The surface scattering of the carriers and phonon scattering can be prevented while suppressing the short channel effect. Resultantly the semiconductor device can have high mobility and high speed.
    Type: Grant
    Filed: December 7, 2004
    Date of Patent: January 8, 2008
    Assignee: Fujitsu Limited
    Inventors: Takashi Mimura, Keiji Ikeda
  • Publication number: 20070243672
    Abstract: The semiconductor device comprises a semiconductor layer 18 formed on an insulation layer 16, a gate electrode 22 formed on the semiconductor layer with a gate insulation film 20 formed therebetween, a source/drain region 24 formed on the semiconductor layer on both sides of the gate electrode, and a semiconductor region 14 buried in the insulation layer 16 in a region below the gate electrode. The surface scattering of the carriers and phonon scattering can be prevented while suppressing the short channel effect. Resultantly the semiconductor device can have high mobility and high speed.
    Type: Application
    Filed: June 7, 2007
    Publication date: October 18, 2007
    Applicant: FUJITSU LIMITED
    Inventors: Takashi Mimura, Keiji Ikeda
  • Publication number: 20070057347
    Abstract: A field-effect transistor that increases the operation speeds of complementary field-effect transistors. Each of an nMOSFET and a pMODFET has a Ge channel and source and drain regions formed of an NiGe layer. The height of Schottky barriers formed at a junction between a channel region and the source region of the nMOSFET and at a junction between the channel region and the drain region of the nMOSFET is changed by very thin high-concentration segregation layers formed by making As atoms, Sb atoms, S atoms, or the like segregate at the time of forming the NiGe layer. As a result, Schottky barrier height suitable for the nMOSFET and the pMODFET can be obtained, thus being capable of realizing high-speed CMOSFETs.
    Type: Application
    Filed: May 2, 2006
    Publication date: March 15, 2007
    Applicant: FUJITSU LIMITED
    Inventor: Keiji Ikeda
  • Publication number: 20070042120
    Abstract: A method of forming a semiconductor layer includes cleaning a substrate having a germanium layer formed as a surface layer, with a solution containing at least one selected from the group consisting of hydrochloric acid, hydrobromic acid, and hydroiodic acid, subjecting the substrate after the cleaning to hydrogen annealing in a CVD chamber, and introducing a deposition gas into the CVD chamber to form a semiconductor layer on the substrate.
    Type: Application
    Filed: July 24, 2006
    Publication date: February 22, 2007
    Inventors: Yoshihiko Moriyama, Keiji Ikeda
  • Patent number: 7019336
    Abstract: In a nitride-system semiconductor, being different from GaAs and Si, Schottky barrier heights ?B change significantly against work functions ?M of metals. Then, for example, on an HEMT in which a buffer layer and a barrier layer constituted by nitride-system semiconductors are sequentially formed on a substrate, and a gate electrode is formed on the barrier layer, when a metal having a relatively large work function ?M is selected as a metal constituting the gate electrode, and the thickness of the barrier layer is adjusted so that the Schottky barrier height ?B becomes larger as compared to a semiconductor surface potential ?S on both sides of the gate electrode, a two-dimensional electron gas cannot exist below the gate electrode even when no recess is formed on a portion immediately beneath the gate electrode on the barrier layer, so that the enhancement operation becomes possible.
    Type: Grant
    Filed: June 21, 2004
    Date of Patent: March 28, 2006
    Assignee: Fujitsu Limited
    Inventors: Yoshimi Yamashita, Akira Endoh, Keiji Ikeda
  • Publication number: 20050280027
    Abstract: A first film of rare-earth metal is formed on a semiconductor region of compound semiconductor exposed on a substrate. A second film essentially comprising silicon is formed on the surface of the first film. The first and second films are heated to silicidate at least a portion of the first film in contact with the second film. It is possible to lower the contact resistance of an ohmic electrode formed on semiconductor having a wide band gap.
    Type: Application
    Filed: July 20, 2005
    Publication date: December 22, 2005
    Applicant: FUJITSU LIMITED
    Inventors: Keiji Ikeda, Yoshimi Yamashita
  • Patent number: 6936487
    Abstract: A first film of rare-earth metal is formed on a semiconductor region of compound semiconductor exposed on a substrate. A second film essentially comprising silicon is formed on the surface of the first film. The first and second films are heated to silicidate at least a portion of the first film in contact with the second film. It is possible to lower the contact resistance of an ohmic electrode formed on semiconductor having a wide band gap.
    Type: Grant
    Filed: May 6, 2003
    Date of Patent: August 30, 2005
    Assignee: Fujitsu Limited
    Inventors: Keiji Ikeda, Yoshimi Yamashita
  • Publication number: 20050085027
    Abstract: The semiconductor device comprises a semiconductor layer 18 formed on an insulation layer 16, a gate electrode 22 formed on the semiconductor layer with a gate insulation film 20 formed therebetween, a source/drain region 24 formed on the semiconductor layer on both sides of the gate electrode, and a semiconductor region 14 buried in the insulation layer 16 in a region below the gate electrode. The surface scattering of the carriers and phonon scattering can be prevented while suppressing the short channel effect. Resultantly the semiconductor device can have high mobility and high speed.
    Type: Application
    Filed: December 7, 2004
    Publication date: April 21, 2005
    Applicant: Fujitsu Limited
    Inventors: Takashi Mimura, Keiji Ikeda