Patents by Inventor Takeshi Kitahara

Takeshi Kitahara 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: 10211068
    Abstract: Preventing a deformation when a metal layer made of copper or copper alloy is brazed on an aluminum-made cooler, a power-module substrate with cooler having low thermal resistance and high bonding reliability is provided: a circuit layer made of copper or copper alloy is bonded on one surface of a ceramic board and a metal layer made of copper or copper alloy is bonded on the other surface of the ceramic board; a second metal layer made of aluminum or aluminum alloy is bonded to the metal layer by solid-phase diffusion; and a cooler made of aluminum alloy is brazed on the second metal layer with Al-based Mg-included brazing material.
    Type: Grant
    Filed: October 9, 2015
    Date of Patent: February 19, 2019
    Assignee: MITSUBISHI MATERIALS CORPORATION
    Inventors: Sotaro Oi, Tomoya Oohiraki, Takeshi Kitahara
  • Patent number: 9862045
    Abstract: To provide a power-module substrate and a manufacturing method thereof in which small voids are reduced at a bonded part and separation can be prevented. Bonding a metal plate of aluminum or aluminum alloy to at least one surface of a ceramic substrate by brazing, when a cross section of the metal plate is observed by a scanning electron microscope in a field of 3000 magnifications in a depth extent of 5 ?m from a bonded interface between the metal plate and the ceramic substrate in a width area of 200 ?m from a side edge of the metal plate, residual-continuous oxide existing continuously by 2 ?m or more along the bonded interface has total length of 70% or less with respect to a length of the field.
    Type: Grant
    Filed: March 27, 2013
    Date of Patent: January 9, 2018
    Assignee: MITSUBISHI MATERIALS CORPORATION
    Inventors: Toshiyuki Nagase, Takeshi Kitahara, Ryo Muranaka
  • Publication number: 20170309499
    Abstract: Preventing a deformation when a metal layer made of copper or copper alloy is brazed on an aluminum-made cooler, a power-module substrate with cooler having low thermal resistance and high bonding reliability is provided: a circuit layer made of copper or copper alloy is bonded on one surface of a ceramic board and a metal layer made of copper or copper alloy is bonded on the other surface of the ceramic board; a second metal layer made of aluminum or aluminum alloy is bonded to the metal layer by solid-phase diffusion; and a cooler made of aluminum alloy is brazed on the second metal layer with Al-based Mg-included brazing material.
    Type: Application
    Filed: October 9, 2015
    Publication date: October 26, 2017
    Applicant: MITSUBISHI MATERIALS CORPORATION
    Inventors: Sotaro Oi, Tomoya Oohiraki, Takeshi Kitahara
  • Publication number: 20150328706
    Abstract: To provide a power-module substrate and a manufacturing method thereof in which small voids are reduced at a bonded part and separation can be prevented. Bonding a metal plate of aluminum or aluminum alloy to at least one surface of a ceramic substrate by brazing, when a cross section of the metal plate is observed by a scanning electron microscope in a field of 3000 magnifications in a depth extent of 5 ?m from a bonded interface between the metal plate and the ceramic substrate in a width area of 200 ?m from a side edge of the metal plate, residual-continuous oxide existing continuously by 2 ?m or more along the bonded interface has total length of 70% or less with respect to a length of the field.
    Type: Application
    Filed: March 27, 2013
    Publication date: November 19, 2015
    Applicant: MITSUBISHI MATERIALS CORPORATION
    Inventors: Toshiyuki Nagase, Takeshi Kitahara, Ryo Muranaka
  • Patent number: 9101063
    Abstract: A power module substrate includes a ceramics substrate composed of Si3N4 having a top face. A metal plate composed of aluminum having a purity of 99.99% or more is joined to the top face of the ceramics substrate with a brazing filler metal which includes a melting-point lowering element interposed therebetween. A high concentration section is formed at a joint interface at which the metal plate is joined to the ceramics substrate, has an oxygen concentration greater than an oxygen concentration in the metal plate and in the ceramics substrate, and has a thickness of less than or equal to 4 nm.
    Type: Grant
    Filed: November 13, 2013
    Date of Patent: August 4, 2015
    Assignee: MITSUBISHI MATERIALS CORPORATION
    Inventors: Yoshirou Kuromitsu, Kazuhiro Akiyama, Takeshi Kitahara, Hiroshi Tonomura
  • Patent number: 9095062
    Abstract: A power module substrate includes a ceramics substrate composed of Al2O3 having a top face. A metal plate composed of aluminum having a purity of 99.99% or more is joined to the top face of the ceramics substrate with a brazing filler metal which includes silicon interposed therebetween. A high concentration section is formed at a joint interface at which the metal plate is joined to the ceramics substrate, and has a silicon concentration that is more than five times the silicon concentration in the metal plate.
    Type: Grant
    Filed: November 13, 2013
    Date of Patent: July 28, 2015
    Assignee: MITSUBISHI MATERIALS CORPORATION
    Inventors: Yoshirou Kuromitsu, Kazuhiro Akiyama, Takeshi Kitahara, Hiroshi Tonomura
  • Patent number: 9079264
    Abstract: Disclosed is a ceramic substrate including silicon in which the concentration of a silicon oxide and a silicon composite oxide in the surface thereof is less than or equal to 2.7 Atom %.
    Type: Grant
    Filed: April 22, 2013
    Date of Patent: July 14, 2015
    Assignee: MITSUBISHI MATERIALS CORPORATION
    Inventors: Hiroshi Tonomura, Takeshi Kitahara, Hiroya Ishizuka, Yoshirou Kuromitsu, Yoshiyuki Nagatomo
  • Publication number: 20150022977
    Abstract: A power module substrate includes: a ceramics substrate having a surface; and a metal plate connected to the surface of the ceramics substrate, composed of aluminum, and including Cu at a joint interface between the ceramics substrate and the metal plate, wherein a Cu concentration at the joint interface is in the range of 0.05 to 5 wt %.
    Type: Application
    Filed: October 10, 2014
    Publication date: January 22, 2015
    Inventors: Yoshirou Kuromitsu, Yoshiyuki Nagatomo, Takeshi Kitahara, Hiroshi Tonomura, Kazuhiro Akiyama
  • Patent number: 8921996
    Abstract: A power module substrate includes: a ceramics substrate having a surface; and a metal plate connected to the surface of the ceramics substrate, composed of aluminum, and including Cu at a joint interface between the ceramics substrate and the metal plate, wherein a Cu concentration at the joint interface is in the range of 0.05 to 5 wt %.
    Type: Grant
    Filed: September 16, 2013
    Date of Patent: December 30, 2014
    Assignee: Mitsubishi Materials Corporation
    Inventors: Yoshirou Kuromitsu, Yoshiyuki Nagatomo, Takeshi Kitahara, Hiroshi Tonomura, Kazuhiro Akiyama
  • Publication number: 20140318831
    Abstract: In a power module substrate, a circuit layer is formed on one surface of an insulating layer, a metal layer is formed on the other surface of the insulating layer, and a body to be bonded can be bonded to the other surface of the metal layer using a flux. A flux component intrusion-preventing layer containing an oxide and a resin is formed at a circumferential edge section of a bonding interface between the insulating layer and the metal layer.
    Type: Application
    Filed: December 11, 2012
    Publication date: October 30, 2014
    Inventors: Kimihito Nishikawa, Shuuji Nishimoto, Takeshi Kitahara, Toshiyuki Nagase
  • Publication number: 20140110771
    Abstract: According to one embodiment, a solid-state imaging device includes a semiconductor substrate including a pixel area and a peripheral circuit area, a first line provided in the peripheral circuit area and on a first principal surface of the semiconductor substrate, a second line provided in the peripheral circuit area and on a second principal surface of the semiconductor substrate, a first through electrode connected to one end of the first line and one end of the second line and passing through the semiconductor substrate, and a second through electrode connected to the other end of the first line and the other end of the second line and passing through the semiconductor substrate.
    Type: Application
    Filed: July 23, 2013
    Publication date: April 24, 2014
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Tomoyuki YODA, Jiro Hayakawa, Ikuko Inoue, Eiji Sato, Takeshi Kitahara
  • Publication number: 20140078684
    Abstract: A power module substrate includes: a ceramics substrate composed of AlN, having a top face; a metal plate composed of pure aluminum and joined to the top face of the ceramics substrate with a brazing filler metal including silicon interposed therebetween; and a high concentration section formed at a joint interface at which the metal plate is joined to the ceramics substrate, having a silicon concentration that is more than five times the silicon concentration in the metal plate.
    Type: Application
    Filed: November 13, 2013
    Publication date: March 20, 2014
    Applicant: MITSUBISHI MATERIALS CORPORATION
    Inventors: Yoshirou Kuromitsu, Kazuhiro Akiyama, Takeshi Kitahara, Hiroshi Tonomura
  • Publication number: 20140071633
    Abstract: A power module substrate includes: a ceramics substrate composed of AlN, having a top face; a metal plate composed of pure aluminum and joined to the top face of the ceramics substrate with a brazing filler metal including silicon interposed therebetween; and a high concentration section formed at a joint interface at which the metal plate is joined to the ceramics substrate, having a silicon concentration that is more than five times the silicon concentration in the metal plate.
    Type: Application
    Filed: November 13, 2013
    Publication date: March 13, 2014
    Applicant: MITSUBISHI MATERIALS CORPORATION
    Inventors: Yoshirou Kuromitsu, Kazuhiro Akiyama, Takeshi Kitahara, Hiroshi Tonomura
  • Patent number: 8637777
    Abstract: A power module substrate having a heatsink, includes: a power module substrate having an insulating substrate having a first face and a second face, a circuit layer formed on the first face, and a metal layer formed on the second face; and a heatsink directly connected to the metal layer, cooling the power module substrate, wherein a ratio B/A is in the range defined by 1.55?B/A?20, where a thickness of the circuit layer is represented as A, and a thickness of the metal layer is represented as B.
    Type: Grant
    Filed: March 11, 2009
    Date of Patent: January 28, 2014
    Assignee: Mitsubishi Materials Corporation
    Inventors: Hiromasa Hayashi, Takeshi Kitahara, Hiroshi Tonomura, Hiroya Ishizuka, Yoshirou Kuromitsu
  • Publication number: 20140015140
    Abstract: A power module substrate includes: a ceramics substrate having a surface; and a metal plate connected to the surface of the ceramics substrate, composed of aluminum, and including Cu at a joint interface between the ceramics substrate and the metal plate, wherein a Cu concentration at the joint interface is in the range of 0.05 to 5 wt %.
    Type: Application
    Filed: September 16, 2013
    Publication date: January 16, 2014
    Applicant: MITSUBISHI MATERIALS CORPORATION
    Inventors: Yoshirou Kuromitsu, Yoshiyuki Nagatomo, Takeshi Kitahara, Hiroshi Tonomura, Kazuhiro Akiyama
  • Patent number: 8609993
    Abstract: A power module substrate includes: a ceramics substrate composed of AlN, having a top face; a metal plate composed of pure aluminum and joined to the top face of the ceramics substrate with a brazing filler metal including silicon interposed therebetween; and a high concentration section formed at a joint interface at which the metal plate is joined to the ceramics substrate, having a silicon concentration that is more than five times the silicon concentration in the metal plate.
    Type: Grant
    Filed: May 15, 2009
    Date of Patent: December 17, 2013
    Assignee: Mitsubishi Materials Corporation
    Inventors: Yoshirou Kuromitsu, Kazuhiro Akiyama, Takeshi Kitahara, Hiroshi Tonomura
  • Patent number: 8564118
    Abstract: A power module substrate includes: a ceramics substrate having a surface; and a metal plate connected to the surface of the ceramics substrate, composed of aluminum, and including Cu at a joint interface between the ceramics substrate and the metal plate, wherein a Cu concentration at the joint interface is in the range of 0.05 to 5 wt %.
    Type: Grant
    Filed: June 5, 2009
    Date of Patent: October 22, 2013
    Assignee: Mitsubishi Materials Corporation
    Inventors: Yoshirou Kuromitsu, Yoshiyuki Nagatomo, Takeshi Kitahara, Hiroshi Tonomura, Kazuhiro Akiyama
  • Publication number: 20130232783
    Abstract: Disclosed is a ceramic substrate including silicon in which the concentration of a silicon oxide and a silicon composite oxide in the surface thereof is less than or equal to 2.7 Atom %.
    Type: Application
    Filed: April 22, 2013
    Publication date: September 12, 2013
    Applicant: MITSUBISHI MATERIALS CORPORATION
    Inventors: Hiroshi Tonomura, Takeshi Kitahara, Hiroya Ishizuka, Yoshirou Kuromitsu, Yoshiyuki Nagatomo
  • Patent number: 8446827
    Abstract: A radio communication terminal includes a link-usage level calculating section that calculates usage level of a radio link, and a data reception continuation/suspension determining section that determines continuation of data reception or suspension of data reception according to the level of usage calculated by the link-usage level calculating section. The link-usage level calculating section calculates a current usage level indicating a level of usage of the radio link associated with current data reception in the radio communication terminal. The data reception continuation/suspension determining section determines continuation of data reception when the current usage level is equal to or higher than a reference level of usage being a threshold and determines suspension of data reception when the current usage level is lower than the reference level of usage.
    Type: Grant
    Filed: March 22, 2010
    Date of Patent: May 21, 2013
    Assignee: KDDI Corporation
    Inventors: Takeshi Kitahara, Hajime Nakamura, Yasuhiko Hiehata
  • Patent number: 8311052
    Abstract: Control of readout of packets from a packet buffer is disclosed in which equal numbers of tokens are removed and used from token buckets having different bucket sizes; tokens are generated at token rates for the token buckets, wherein each token rate is preset such that the larger the token bucket size, the lower the token rate, and the generated tokens are added to the token buckets; a used-token count is measured for each token bucket, and a stored-token count is measured for each token bucket, with the stored-token count given a negative value if each token bucket is empty; and a number of data packets are read out of the packet buffer, which depends on the measured value of the used-token count for each token buffer.
    Type: Grant
    Filed: June 16, 2010
    Date of Patent: November 13, 2012
    Assignee: KDDI Corporation
    Inventors: Hajime Nakamura, Norihiro Fukumoto, Takeshi Kitahara