Patents by Inventor Masato Koyama

Masato Koyama 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: 7986014
    Abstract: A semiconductor device includes a semiconductor substrate, an nMISFET formed on the substrate, the nMISFET including a first dielectric formed on the substrate and a first metal gate electrode formed on the first dielectric and formed of one metal element selected from Ti, Zr, Hf, Ta, Sc, Y, a lanthanoide and actinide series and of one selected from boride, silicide and germanide compounds of the one metal element, and a pMISFET formed on the substrate, the pMISFET including a second dielectric formed on the substrate and a second metal gate electrode formed on the second dielectric and made of the same material as that of the first metal gate electrode, at least a portion of the second dielectric facing the second metal gate electrode being made of an insulating material different from that of at least a portion of the first dielectric facing the first metal gate electrode.
    Type: Grant
    Filed: December 22, 2009
    Date of Patent: July 26, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Reika Ichihara, Yoshinori Tsuchiya, Masato Koyama, Akira Nishiyama
  • Patent number: 7968956
    Abstract: A semiconductor device includes a semiconductor substrate, a p-channel MIS transistor formed on the substrate, the p-channel transistor having a first gate dielectric formed on the substrate and a first gate electrode layer formed on the first dielectric, and an n-channel MIS transistor formed on the substrate, the n-channel transistor having a second gate dielectric formed on the substrate and a second gate electrode layer formed on the second dielectric. A bottom layer of the first gate electrode layer in contact with the first gate dielectric and a bottom layer of the second gate electrode layer in contact with the second gate dielectric have the same orientation and the same composition including Ta and C, and a mole ratio of Ta to a total of C and Ta, (Ta/(Ta+C)), is larger than 0.5.
    Type: Grant
    Filed: February 19, 2009
    Date of Patent: June 28, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kosuke Tatsumura, Masakazu Goto, Reika Ichihara, Masato Koyama, Shigeru Kawanaka, Kazuaki Nakajima
  • Patent number: 7964489
    Abstract: A semiconductor device includes: a p-channel MIS transistor including: a first insulating layer formed on a semiconductor region between a source region and a drain region, and containing at least silicon and oxygen; a second insulating layer formed on the first insulating layer, and containing hafnium, silicon, oxygen, and nitrogen, and a first gate electrode formed on the second insulating layer. The first and second insulating layers have a first and second region respectively. The first and second regions are in a 0.3 nm range in the film thickness direction from an interface between the first insulating layer and the second insulating layer. Each of the first and second regions include aluminum atoms with a concentration of 1×1020 cm?3 or more to 1×1022 cm?3 or less.
    Type: Grant
    Filed: June 25, 2009
    Date of Patent: June 21, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masato Koyama, Yoshinori Tsuchiya, Yuuichi Kamimuta, Reika Ichihara, Katsuyuki Sekine
  • Patent number: 7960793
    Abstract: According to one embodiment, it is possible to provide a semiconductor device provided with an MIS transistor which has an effective work function being, as much as possible, suitable for low threshold operation. A CMIS device provided with an electrode having an optimal effective work function and enabling low threshold operation to achieve by producing an in-gap level by the addition of a high valence metal in an Hf (or Zr) oxide and changing a position of the in-gap level by nitrogen or fluorine or the like has been realized.
    Type: Grant
    Filed: February 13, 2009
    Date of Patent: June 14, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tatsuo Shimizu, Masato Koyama
  • Patent number: 7943984
    Abstract: A nonvolatile semiconductor memory apparatus includes: a memory element including: a semiconductor substrate; a source region and a drain region formed at a distance from each other in the semiconductor substrate; a first insulating film formed on a portion of the semiconductor substrate located between the source region and the drain region, having sites that perform electron trapping and releasing and are formed by adding an element different from a base material, and including insulating layers having different dielectric constants, the sites having a higher level than a Fermi level of a material forming the semiconductor substrate; a charge storage film formed on the first insulating film; a second insulating film formed on the charge storage film; and a control gate electrode formed on the second insulating film.
    Type: Grant
    Filed: September 18, 2008
    Date of Patent: May 17, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masahiro Koike, Yuuichiro Mitani, Yasushi Nakasaki, Masato Koyama
  • Publication number: 20110089765
    Abstract: A power converting apparatus includes a first inverter circuit including a high-voltage first DC voltage source and operated at a low frequency using Si IGBTs having a high withstand voltage exceeding 1000 V and a second inverter circuit including a low-voltage capacitor operated by high-frequency PWM using SiC MOSFETs having a low withstand voltage, wherein an AC side of the first inverter circuit is connected in series to an AC side of the second inverter circuit. The power converting apparatus outputs AC power having a prescribed voltage waveform obtained from the sum of voltages generated by the first and second inverter circuits.
    Type: Application
    Filed: March 18, 2009
    Publication date: April 21, 2011
    Applicant: Mitsubishi Electric Corporation
    Inventors: Akihiko Iwata, Takeshi Oi, Masato Koyama
  • Patent number: 7898015
    Abstract: An insulating film includes a first metal, oxygen, fluorine and one of a second metal or nitrogen, and satisfies {k×[X]?[F]}/2?8.4 atomic %, wherein the fluorine amount [F], the one element amount [X], and a valence number difference k between the first and second metals or between oxygen and nitrogen.
    Type: Grant
    Filed: March 21, 2007
    Date of Patent: March 1, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tatsuo Shimizu, Masato Koyama
  • Patent number: 7863695
    Abstract: A complementary semiconductor device includes a semiconductor substrate, a first semiconductor region formed on a surface of the semiconductor substrate, a second semiconductor region formed on the surface of the semiconductor substrate apart from the first semiconductor region, an n-MIS transistor having a first gate insulating film including La and Al, formed on the first semiconductor region, and a first gate electrode formed on the gate insulating film, and a p-MIS transistor having a second gate insulating film including La and Al, formed on the second semiconductor region, and a second gate electrode formed on the gate insulating film, an atomic density ratio Al/La in the second gate insulating film being larger than an atomic density ratio Al/La in the first gate insulating film.
    Type: Grant
    Filed: August 28, 2008
    Date of Patent: January 4, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masamichi Suzuki, Masato Koyama, Yoshinori Tsuchiya, Hirotaka Nishino, Reika Ichihara, Akira Takashima
  • Patent number: 7834408
    Abstract: It is possible to prevent the deterioration of device characteristic as much as possible. A semiconductor device includes: a semiconductor substrate; a gate insulating film provided above the semiconductor substrate and containing a metal, oxygen and an additive element; a gate electrode provided above the gate insulating film; and source/drain regions provided in the semiconductor substrate on both sides of the gate electrode. The additive element is at least one element selected from elements of Group 5, 6, 15, and 16 at a concentration of 0.003 atomic % or more but 3 atomic % or less.
    Type: Grant
    Filed: January 22, 2009
    Date of Patent: November 16, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yuuichi Kamimuta, Akira Nishiyama, Yasushi Nakasaki, Tsunehiro Ino, Masato Koyama
  • Patent number: 7825458
    Abstract: A nonvolatile semiconductor memory includes a source area and a drain area provided on a semiconductor substrate with a gap which serves as a channel area, a first insulating layer, a charge accumulating layer, a second insulating layer (block layer) and a control electrode, formed successively on the channel area, and the second insulating layer is formed by adding an appropriate amount of high valence substance into base material composed of substance having a sufficiently higher dielectric constant than the first insulating layer so as to accumulate a large amount of negative charges in the block layer by localized state capable of trapping electrons, so that the high dielectric constant of the block layer and the high electronic barrier are achieved at the same time.
    Type: Grant
    Filed: March 18, 2008
    Date of Patent: November 2, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tatsuo Shimizu, Koichi Muraoka, Masato Koyama, Shoko Kikuchi
  • Publication number: 20100258880
    Abstract: A semiconductor device includes: an n-channel MIS transistor and a p-channel MIS transistor. An n-channel MIS transistor includes: a first gate insulating film having an amorphous layer or an epitaxial layer formed on a p-type semiconductor region between a first source/drain regions; and a first gate electrode having a stack structure formed with a first metal layer and a first compound layer. The first metal layer is formed on the first gate insulating film and made of a first metal having a work function of 4.3 eV or smaller, and the first compound layer is formed on the first metal layer and contains a compound of a second metal and a IV-group semiconductor. The second metal is different from the first metal. A p-channel MIS transistor includes a second gate electrode having a second compound layer containing a compound of the same composition as the first compound layer.
    Type: Application
    Filed: June 28, 2010
    Publication date: October 14, 2010
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Yoshinori TSUCHIYA, Masato Koyama, Masahiko Yoshiki
  • Patent number: 7807990
    Abstract: A semiconductor device includes: a p-channel MIS transistor including: a first insulating layer formed on a semiconductor region between a source region and a drain region, and containing at least silicon and oxygen; a second insulating layer formed on the first insulating layer, and containing hafnium, silicon, oxygen, and nitrogen, and a first gate electrode formed on the second insulating layer. The first and second insulating layers have a first and second region respectively. The first and second regions are in a 0.3 nm range in the film thickness direction from an interface between the first insulating layer and the second insulating layer. Each of the first and second regions include aluminum atoms with a concentration of 1×1020 cm?3 or more to 1×1022 cm?3 or less.
    Type: Grant
    Filed: May 24, 2007
    Date of Patent: October 5, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masato Koyama, Yoshinori Tsuchiya, Yuuichi Kamimuta, Reika Ichihara, Katsuyuki Sekine
  • Patent number: 7804145
    Abstract: It is made possible to provide a semiconductor device that has the effective work function of the connected metal optimized at the interface between a semiconductor and the metal. A semiconductor device includes: a semiconductor film; an oxide film formed on the semiconductor film, the oxide film including at least one of Hf and Zr, and at least one element selected from the group consisting of V, Cr, Mn, Nb, Mo, Tc, W, and Re being added to the oxide film; and a metal film formed on the oxide film.
    Type: Grant
    Filed: February 19, 2009
    Date of Patent: September 28, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tatsuo Shimizu, Masato Koyama
  • Publication number: 20100210100
    Abstract: It is made possible to provide a method for manufacturing a semiconductor device that includes CMISs each having a low threshold voltage Vth and a Ni-FUSI/SiON or high-k gate insulating film structure. The method comprises: forming a p-type semiconductor region and an n-type semiconductor region insulated from each other in a substrate; forming a first and second gate insulating films on the p-type and n-type semiconductor regions, respectively; forming a first nickel silicide having a composition of Ni/Si<31/12 above the first gate insulating film, and a second nickel silicide having a composition of Ni/Si?31/12 on the second gate insulating film; and segregating aluminum at an interface between the first nickel silicide and the first gate insulating film by diffusing aluminum through the first nickel silicide.
    Type: Application
    Filed: April 23, 2010
    Publication date: August 19, 2010
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Masato Koyama, Yoshinori Tsuchiya, Seiji Inumiya
  • Patent number: 7768077
    Abstract: A semiconductor device includes: an n-channel MIS transistor and a p-channel MIS transistor. An n-channel MIS transistor includes: a first gate insulating film having an amorphous layer or an epitaxial layer formed on a p-type semiconductor region between a first source/drain regions; and a first gate electrode having a stack structure formed with a first metal layer and a first compound layer. The first metal layer is formed on the first gate insulating film and made of a first metal having a work function of 4.3 eV or smaller, and the first compound layer is formed on the first metal layer and contains a compound of a second metal and a IV-group semiconductor. The second metal is different from the first metal. A p-channel MIS transistor includes a second gate electrode having a second compound layer containing a compound of the same composition as the first compound layer.
    Type: Grant
    Filed: December 7, 2009
    Date of Patent: August 3, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshinori Tsuchiya, Masato Koyama, Masahiko Yoshiki
  • Patent number: 7763946
    Abstract: A semiconductor device includes: a substrate and a p-channel MIS transistor. The p-channel MIS transistor includes: an n-type semiconductor region formed in the substrate; p-type first source and drain regions formed at a distance from each other in the n-type semiconductor region; a first gate insulating film formed on the n-type semiconductor region between the first source region and the first drain region; and a first gate electrode formed on the first gate insulating film. The first gate electrode includes a first nickel silicide layer having a Ni/Si composition ratio of 1 or greater, and a silicide layer formed on the first nickel silicide layer. The silicide layer contains a metal having a larger absolute value of oxide formation energy than that of Si, and a composition ratio of the metal to Si is smaller than the Ni/Si composition ratio.
    Type: Grant
    Filed: October 12, 2007
    Date of Patent: July 27, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshinori Tsuchiya, Masato Koyama
  • Patent number: 7755089
    Abstract: A semiconductor device includes a semiconductor substrate, p-type first and n-type second semiconductor regions formed on the substrate so as to be insulated with each other, n-channel and p-channel MOS transistors formed on the first and second semiconductor regions, the n-channel transistor including a first pair of source/drain regions formed on the first semiconductor region, a first gate insulator formed in direct contact with the first semiconductor region and formed as an amorphous insulator containing at least La, and a first gate electrode formed on the first gate insulator, the p-channel MOS transistor including a second pair of source/drain regions formed opposite to each other on the second semiconductor region, a second gate insulator including a silicon oxide film and the amorphous insulating film formed thereon on the second semiconductor region, and a second gate electrode formed on the second gate insulator.
    Type: Grant
    Filed: September 20, 2007
    Date of Patent: July 13, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masamichi Suzuki, Masato Koyama
  • Publication number: 20100171184
    Abstract: A semiconductor device includes a semiconductor substrate, an nMISFET formed on the substrate, the nMISFET including a first dielectric formed on the substrate and a first metal gate electrode formed on the first dielectric and formed of one metal element selected from Ti, Zr, Hf, Ta, Sc, Y, a lanthanoide and actinide series and of one selected from boride, silicide and germanide compounds of the one metal element, and a pMISFET formed on the substrate, the pMISFET including a second dielectric formed on the substrate and a second metal gate electrode formed on the second dielectric and made of the same material as that of the first metal gate electrode, at least a portion of the second dielectric facing the second metal gate electrode being made of an insulating material different from that of at least a portion of the first dielectric facing the first metal gate electrode.
    Type: Application
    Filed: December 22, 2009
    Publication date: July 8, 2010
    Inventors: Reika Ichihara, Yoshinori Tsuchiya, Masato Koyama, Akira Nishiyama
  • Patent number: 7745888
    Abstract: A semiconductor device includes a substrate, a p-channel MIS transistor formed on an n-type well on the substrate, having a first gate dielectric and a first gate electrode formed thereon and formed of a Ta—C alloy wherein a crystal orientation ratio of a TaC (111) face in a film thickness direction [TaC (111) face/{TaC (111) face+TaC (200) face}] is 80% or more, and an n-channel MIS transistor formed on a p-type well on the substrate, having a second gate dielectric and a second gate electrode formed thereon and formed of a Ta—C alloy wherein a crystal orientation ratio of a TaC (111) face in a film thickness direction [TaC (111) face/{TaC (111) face+TaC (200) face}] is 60% or less.
    Type: Grant
    Filed: September 10, 2008
    Date of Patent: June 29, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masato Koyama, Reika Ichihara, Yoshinori Tsuchiya, Yuuichi Kamimuta, Akira Nishiyama
  • Publication number: 20100155851
    Abstract: There is disclosed a semiconductor device comprising a P-channel MIS transistor which includes an N-type semiconductor layer, a first gate insulating layer formed on the N-type semiconductor layer and containing a carbon compound of a metal, and an N-channel MIS transistor which includes a P-type semiconductor layer, a second gate insulating layer formed on the P-type semiconductor layer, and a second gate electrode formed on the second gate insulating layer.
    Type: Application
    Filed: March 9, 2010
    Publication date: June 24, 2010
    Inventors: Masato KOYAMA, Akira Nishiyama, Yoshinori Tsuchiya, Reika Ichihara