Patents by Inventor Masaki Koyama

Masaki 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).

  • Publication number: 20140361333
    Abstract: When a semiconductor substrate of a semiconductor device is viewed from above, an isolation region, an IGBT region, and a diode region are all formed adjacent to each other. A deep region that is connected to a body region and an anode region is formed in the isolation region. A drift region is formed extending across the isolation region, the IGBT region, and the diode region, inside the semiconductor substrate. A collector region that extends across the isolation region, the IGBT region and the diode region, and a cathode region positioned in the diode region, are formed in a region exposed on a lower surface of the semiconductor substrate. A boundary between the collector region and the cathode region is in the diode region, in a cross-section that cuts across a boundary between the isolation region and the diode region, and divides the isolation region and the diode region.
    Type: Application
    Filed: January 23, 2013
    Publication date: December 11, 2014
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Keisuke Kimura, Satoru Kameyama, Masaki Koyama, Sachiko Aoi
  • Patent number: 8871610
    Abstract: To increase adhesion between a single crystal semiconductor layer and a base substrate and to reduce bonding defects therebetween. To perform radical treatment on a surface of a semiconductor substrate to form a first insulating film on the semiconductor substrate; irradiate the semiconductor substrate with accelerated ions through the first insulating film to form an embrittlement region in the semiconductor substrate; form a second insulating film on the first insulating film; perform heat treatment after bonding a surface of the second insulating film and a surface of the base substrate to perform separation along the embrittlement region so that a semiconductor layer is formed over the base substrate with the first and second insulating films interposed therebetween; etch the semiconductor layer; and irradiate the semiconductor layer on which the etching is performed with a laser beam.
    Type: Grant
    Filed: September 29, 2009
    Date of Patent: October 28, 2014
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Akihisa Shimomura, Masaki Koyama, Eiji Higa
  • Publication number: 20140294643
    Abstract: A refrigerant compressor includes a compressor mechanism part 2, and a motor and a crank shaft 101 for driving the compressor mechanism part, in a sealed case 100, and includes sliding bearings 103, 104, and 105 at least either in an engagement part between the compressor mechanism part and the crank shaft or in a rotation support part of the crank shaft. Further, an unleaded resin impregnation material is used for at least one of the sliding bearings, the crank shaft is made of a ferrous material, and a hard carbon film including hydrogen is formed on a part of the crank shaft sliding with the sliding bearing using the unleaded resin impregnation material.
    Type: Application
    Filed: February 6, 2014
    Publication date: October 2, 2014
    Applicant: Hitachi, Ltd.
    Inventors: Masaki KOYAMA, Yuichi YANAGASE
  • Publication number: 20140284597
    Abstract: To improve crystallinity of an oxide semiconductor. To provide a crystalline oxide semiconductor film in which a crystallized region extends to the interface with a base or the vicinity of the interface, and to provide a method for forming the oxide semiconductor film. An oxide semiconductor film containing indium, gallium, and zinc is formed, and the oxide semiconductor film is irradiated with an energy beam, thereby being heated. Note that the oxide semiconductor film includes a c-axis aligned crystal region or microcrystal.
    Type: Application
    Filed: March 13, 2014
    Publication date: September 25, 2014
    Applicant: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Akihisa SHIMOMURA, Takahisa ISHIYAMA, Masaki KOYAMA, Erumu KIKUCHI, Takuya HIROHASHI, Masashi OOTA
  • Patent number: 8772128
    Abstract: A single crystal semiconductor substrate is irradiated with ions that are generated by exciting a hydrogen gas and are accelerated with an ion doping apparatus, thereby forming a damaged region that contains a large amount of hydrogen. After the single crystal semiconductor substrate and a supporting substrate are bonded, the single crystal semiconductor substrate is heated to be separated along the damaged region. While a single crystal semiconductor layer separated from the single crystal semiconductor substrate is heated, this single crystal semiconductor layer is irradiated with a laser beam. The single crystal semiconductor layer undergoes re-single-crystallization by being melted through laser beam irradiation, thereby recovering its crystallinity and planarizing the surface of the single crystal semiconductor layer.
    Type: Grant
    Filed: October 7, 2008
    Date of Patent: July 8, 2014
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Shunpei Yamazaki, Junpei Momo, Fumito Isaka, Eiji Higa, Masaki Koyama, Akihisa Shimomura
  • Patent number: 8716746
    Abstract: In a semiconductor device, an IGBT cell includes a trench passing through a base layer of a semiconductor substrate to a drift layer of the semiconductor substrate, a gate insulating film on an inner surface of the trench, a gate electrode on the gate insulating film, a first conductivity-type emitter region in a surface portion of the base layer, and a second conductivity-type first contact region in the surface portion of the base layer. The IGBT cell further includes a first conductivity-type floating layer disposed within the base layer to separate the base layer into a first portion including the emitter region and the first contact region and a second portion adjacent to the drift layer, and an interlayer insulating film disposed to cover an end of the gate electrode. A diode cell includes a second conductivity-type second contact region in the surface portion of the base layer.
    Type: Grant
    Filed: August 9, 2011
    Date of Patent: May 6, 2014
    Assignees: DENSO CORPORATION, Toyota Jidosha Kabushiki Kaisha
    Inventors: Masaki Koyama, Yasushi Ookura, Akitaka Soeno, Tatsuji Nagaoka, Takahide Sugiyama, Sachiko Aoi, Hiroko Iguchi
  • Publication number: 20140056727
    Abstract: A refrigerant compressor includes a sealed case 9, a compression mechanism 2 and a motor part 16 contained in the sealed case, and an oil reservoir 53 formed in a lower portion of the sealed case. The refrigerant compressor further includes an oil supply pipe 62 which links the oil reservoir and a suction side of the compression mechanism by passage and introduces oil in the oil reservoir to the suction side, an oil supply amount adjusting means 61 which is provided on the oil supply pipe and adjusts an amount of oil supply supplied to the suction side, a rotational speed detecting means which detects a rotational speed of the motor part, and an oil supply amount controlling unit 80 which controls the oil supply amount adjusting means according to a rotational speed detected by the rotational speed detecting means.
    Type: Application
    Filed: April 25, 2011
    Publication date: February 27, 2014
    Applicant: Hitachi, Ltd.
    Inventors: Masaki Koyama, Eiji Sato
  • Patent number: 8609502
    Abstract: In a method of manufacturing a semiconductor device, a semiconductor substrate of a first conductivity type having first and second surfaces is prepared. Second conductivity type impurities for forming a collector layer are implanted to the second surface using a mask that has an opening at a portion where the collector layer will be formed. An oxide layer is formed by enhanced-oxidizing the collector layer. First conductivity type impurities for forming a first conductivity type layer are implanted to the second surface using the oxide layer as a mask. A support base is attached to the second surface and a thickness of the semiconductor substrate is reduced from the first surface. An element part including a base region, an emitter region, a plurality of trenches, a gate insulating layer, a gate electrode, and a first electrode is formed on the first surface of the semiconductor substrate.
    Type: Grant
    Filed: June 18, 2013
    Date of Patent: December 17, 2013
    Assignee: DENSO CORPORATION
    Inventors: Masaki Koyama, Yutaka Fukuda
  • Patent number: 8604545
    Abstract: Methods for manufacturing a semiconductor substrate and a semiconductor device by which a high-performance semiconductor element can be formed are provided. A single crystal semiconductor substrate including an embrittlement layer and a base substrate are bonded to each other with an insulating layer interposed therebetween, and the single crystal semiconductor substrate is separated along the embrittlement layer by heat treatment to fix a single crystal semiconductor layer over the base substrate. Next, a plurality of regions of a monitor substrate are irradiated with laser light under conditions of different energy densities, and carbon concentration distribution and hydrogen concentration distribution in a depth direction of each region of the single crystal semiconductor layer which has been irradiated with the laser light is measured.
    Type: Grant
    Filed: January 21, 2011
    Date of Patent: December 10, 2013
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Akihisa Shimomura, Masaki Koyama, Motoki Nakashima
  • Publication number: 20130320332
    Abstract: A transistor including an oxide semiconductor film, which has stable electric characteristics is provided. A transistor including an oxide semiconductor film, which has excellent on-state characteristics is also provided. A semiconductor device in which an oxide semiconductor film having low resistance is formed and the resistance of a channel region of the oxide semiconductor film is increased. Note that an oxide semiconductor film is subjected to a process for reducing the resistance to have low resistance. The process for reducing the resistance of the oxide semiconductor film may be a laser process or heat treatment at a temperature higher than or equal to 450° C. and lower than or equal to 740° C., for example. A process for increasing the resistance of the channel region of the oxide semiconductor film having low resistance may be performed by plasma oxidation or implantation of oxygen ions, for example.
    Type: Application
    Filed: May 20, 2013
    Publication date: December 5, 2013
    Applicant: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Suguru HONDO, Akihisa SHIMOMURA, Masaki KOYAMA, Motomu KURATA, Kazuya HANAOKA, Sho NAGAMATSU, Kosei NEI, Toru HASEGAWA
  • Publication number: 20130316498
    Abstract: In a method of manufacturing a semiconductor device, a semiconductor substrate of a first conductivity type having first and second surfaces is prepared. Second conductivity type impurities for forming a collector layer are implanted to the second surface using a mask that has an opening at a portion where the collector layer will be formed. An oxide layer is formed by enhanced-oxidizing the collector layer. First conductivity type impurities for forming a first conductivity type layer are implanted to the second surface using the oxide layer as a mask. A support base is attached to the second surface and a thickness of the semiconductor substrate is reduced from the first surface. An element part including a base region, an emitter region, a plurality of trenches, a gate insulating layer, a gate electrode, and a first electrode is formed on the first surface of the semiconductor substrate.
    Type: Application
    Filed: June 18, 2013
    Publication date: November 28, 2013
    Applicant: DENSO CORPORATION
    Inventors: Masaki KOYAMA, Yutaka FUKUDA
  • Patent number: 8507352
    Abstract: In a method of manufacturing a semiconductor device, a semiconductor substrate of a first conductivity type having first and second surfaces is prepared. Second conductivity type impurities for forming a collector layer are implanted to the second surface using a mask that has an opening at a portion where the collector layer will be formed. An oxide layer is formed by enhanced-oxidizing the collector layer. First conductivity type impurities for forming a first conductivity type layer are implanted to the second surface using the oxide layer as a mask. A support base is attached to the second surface and a thickness of the semiconductor substrate is reduced from the first surface. An element part including a base region, an emitter region, a plurality of trenches, a gate insulating layer, a gate electrode, and a first electrode is formed on the first surface of the semiconductor substrate.
    Type: Grant
    Filed: November 30, 2009
    Date of Patent: August 13, 2013
    Assignee: DENSO CORPORATION
    Inventors: Masaki Koyama, Yutaka Fukuda
  • Patent number: 8481393
    Abstract: A semiconductor substrate is irradiated with accelerated hydrogen ions, thereby forming a damaged region including a large amount of hydrogen. After a single crystal semiconductor substrate and a supporting substrate are bonded to each other, the semiconductor substrate is heated, so that the single crystal semiconductor substrate is separated in the damaged region. A single crystal semiconductor layer which is separated from the single crystal semiconductor substrate is irradiated with a laser beam. The single crystal semiconductor layer is melted by laser beam irradiation, whereby the single crystal semiconductor layer is recrystallized to recover its crystallinity and to planarized a surface of the single crystal semiconductor layer. After the laser beam irradiation, the single crystal semiconductor layer is heated at a temperature at which the single crystal semiconductor layer is not melted, so that the lifetime of the single crystal semiconductor layer is improved.
    Type: Grant
    Filed: July 27, 2010
    Date of Patent: July 9, 2013
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Masaki Koyama, Fumito Isaka, Akihisa Shimomura, Junpei Momo
  • Patent number: 8421184
    Abstract: A semiconductor device includes: a semiconductor substrate having a first semiconductor layer and a second semiconductor layer formed on a first surface; a diode having a first electrode and a second electrode; a control pad; a control electrode electrically coupled with the control pad; and an insulation member. The first electrode is formed on a second surface of the first semiconductor layer. The second electrode is formed on the first surface. Current flows between the first electrode and the second electrode. The control pad is arranged on the first surface so that the pad inputs a control signal for controlling an injection amount of a carrier into the first semiconductor layer. The insulation member insulates between the control electrode and the second electrode and between the control electrode and the semiconductor substrate.
    Type: Grant
    Filed: May 17, 2010
    Date of Patent: April 16, 2013
    Assignee: DENSO CORPORATION
    Inventors: Masaki Koyama, Yoshiko Fukuda, Yuji Fukuda, Mika Ootsuki
  • Patent number: 8377804
    Abstract: To provide a semiconductor substrate in which a semiconductor element having favorable crystallinity and high performance can be formed. A single crystal semiconductor substrate having an embrittlement layer and a base substrate are bonded with an insulating layer interposed therebetween; the single crystal semiconductor substrate is separated along the embrittlement layer by heat treatment; a single crystal semiconductor layer is fixed to the base substrate; the single crystal semiconductor layer is irradiated with a laser beam; the single crystal semiconductor layer is in a partially melted state to be recrystallized; and crystal defects are repaired. In addition, the energy density of a laser beam with which the best crystallinity of the single crystal semiconductor layer is obtained is detected by a microwave photoconductivity decay method.
    Type: Grant
    Filed: September 29, 2009
    Date of Patent: February 19, 2013
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Junpei Momo, Kosei Nei, Hiroaki Honda, Masaki Koyama, Akihisa Shimomura
  • Publication number: 20130009147
    Abstract: In an oxide semiconductor film formed over an insulating surface, an amorphous region remains in the vicinity of the interface with the base, which is thought to cause a variation in the characteristics of a transistor and the like. A base surface or film touching the oxide semiconductor film is formed of a material having a melting point higher than that of a material used for the oxide semiconductor film. Accordingly, a crystalline region is allowed to exist in the vicinity of the interface with the base surface or film touching the oxide semiconductor film. An insulating metal oxide is used for the base surface or film touching the oxide semiconductor film. The metal oxide used here is an aluminum oxide, gallium oxide, or the like that is a material belonging to the same group as the material of the oxide semiconductor film.
    Type: Application
    Filed: June 28, 2012
    Publication date: January 10, 2013
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Masaki KOYAMA, Kosei NEI, Akihisa SHIMOMURA, Suguru HONDO, Toru HASEGAWA
  • Patent number: 8343847
    Abstract: To prevent, in the case of irradiating a single crystal semiconductor layer with a laser beam, an impurity element from being taken into the single crystal semiconductor layer at the time of laser irradiation.
    Type: Grant
    Filed: October 8, 2009
    Date of Patent: January 1, 2013
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Masaki Koyama, Junpei Momo, Eiji Higa, Hiroaki Honda, Tamae Moriwaka, Akihisa Shimomura
  • Patent number: 8318587
    Abstract: It is an object to provide a method for manufacturing an SOI substrate in which reduction in yield can be suppressed while impurity diffusion into a semiconductor film is suppressed. A semiconductor substrate provided with an oxide film is formed by thermally oxidizing the surface of the semiconductor substrate. Plasma is generated under an atmosphere of a gas containing nitrogen atoms and plasma nitridation is performed on part of the oxide film, so that a semiconductor substrate in which an insulating film containing nitrogen atoms is formed over the oxide film is obtained. After bonding the insulating film containing nitrogen atoms and a glass substrate to each other, the semiconductor substrate is split, whereby an SOI substrate in which the insulating film containing nitrogen atoms, the oxide film, a thin semiconductor film are stacked in this order is formed.
    Type: Grant
    Filed: August 31, 2010
    Date of Patent: November 27, 2012
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Akihisa Shimomura, Masaki Koyama, Toru Hasegawa
  • Patent number: 8314018
    Abstract: A first embrittlement layer is formed by doping a first single-crystal semiconductor substrate with a first ion; a second embrittlement layer is formed by doping a second single-crystal semiconductor substrate with a second ion; the first and second single-crystal semiconductor substrates are bonded to each other; the first single-crystal semiconductor film is formed over the second single-crystal semiconductor substrate by a first heat treatment; an insulating substrate is bonded over the first single-crystal semiconductor film; and the first and second single-crystal semiconductor films are formed over the insulating substrate by a second heat treatment. A dose of the first ion is higher than that of the second ion and a temperature of the first heat treatment is lower than that of the second heat treatment.
    Type: Grant
    Filed: October 8, 2010
    Date of Patent: November 20, 2012
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Akihisa Shimomura, Naoki Okuno, Masaki Koyama, Yasuhiro Jinbo
  • Patent number: 8216914
    Abstract: An object is to provide a method for manufacturing an SOI substrate including a semiconductor film with high planarity and high crystallinity. After a single crystal semiconductor film is formed over an insulating film by a separation step, a natural oxide film existing on a surface of the semiconductor film is removed and the semiconductor film is irradiated with first laser light and second laser light under an inert gas atmosphere or a reduced-pressure atmosphere. The number of shots of the first laser light that is emitted to an arbitrary point in the semiconductor film is greater than or equal to 7, preferably greater than or equal to 10 and less than or equal to 100. The number of shots of the second laser light that is emitted to an arbitrary point in the semiconductor film is greater than 0 and less than or equal to 2.
    Type: Grant
    Filed: August 31, 2010
    Date of Patent: July 10, 2012
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Masaki Koyama, Kosei Nei, Toru Hasegawa, Junpei Momo, Eiji Higa