Patents by Inventor Kosei Nei

Kosei Nei 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: 20180102420
    Abstract: To improve the electrical characteristics of a semiconductor device including an oxide semiconductor, and to provide a highly reliable semiconductor device with a small variation in electrical characteristics. The semiconductor device includes a first insulating film, a first barrier film over the first insulating film, a second insulating film over the first barrier film, and a first transistor including a first oxide semiconductor film over the second insulating film. The amount of hydrogen molecules released from the first insulating film at a given temperature higher than or equal to 400° C., which is measured by thermal desorption spectroscopy, is less than or equal to 130% of the amount of released hydrogen molecules at 300° C. The second insulating film includes a region containing oxygen at a higher proportion than oxygen in the stoichiometric composition.
    Type: Application
    Filed: October 2, 2017
    Publication date: April 12, 2018
    Inventors: Yoshinori ANDO, Hidekazu MIYAIRI, Naoto YAMADE, Asako HIGA, Miki SUZUKI, Yoshinori IEDA, Yasutaka SUZUKI, Kosei NEI, Shunpei YAMAZAKI
  • Patent number: 9780201
    Abstract: To improve the electrical characteristics of a semiconductor device including an oxide semiconductor, and to provide a highly reliable semiconductor device with a small variation in electrical characteristics. The semiconductor device includes a first insulating film, a first barrier film over the first insulating film, a second insulating film over the first barrier film, and a first transistor including a first oxide semiconductor film over the second insulating film. The amount of hydrogen molecules released from the first insulating film at a given temperature higher than or equal to 400° C., which is measured by thermal desorption spectroscopy, is less than or equal to 130% of the amount of released hydrogen molecules at 300° C. The second insulating film includes a region containing oxygen at a higher proportion than oxygen in the stoichiometric composition.
    Type: Grant
    Filed: July 29, 2016
    Date of Patent: October 3, 2017
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Yoshinori Ando, Hidekazu Miyairi, Naoto Yamade, Asako Higa, Miki Suzuki, Yoshinori Ieda, Yasutaka Suzuki, Kosei Nei, Shunpei Yamazaki
  • Publication number: 20160336433
    Abstract: To improve the electrical characteristics of a semiconductor device including an oxide semiconductor, and to provide a highly reliable semiconductor device with a small variation in electrical characteristics. The semiconductor device includes a first insulating film, a first barrier film over the first insulating film, a second insulating film over the first barrier film, and a first transistor including a first oxide semiconductor film over the second insulating film. The amount of hydrogen molecules released from the first insulating film at a given temperature higher than or equal to 400° C., which is measured by thermal desorption spectroscopy, is less than or equal to 130% of the amount of released hydrogen molecules at 300° C. The second insulating film includes a region containing oxygen at a higher proportion than oxygen in the stoichiometric composition.
    Type: Application
    Filed: July 29, 2016
    Publication date: November 17, 2016
    Inventors: Yoshinori ANDO, Hidekazu MIYAIRI, Naoto YAMADE, Asako HIGA, Miki SUZUKI, Yoshinori IEDA, Yasutaka SUZUKI, Kosei NEI, Shunpei YAMAZAKI
  • Patent number: 9496138
    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: Grant
    Filed: June 28, 2012
    Date of Patent: November 15, 2016
    Assignee: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Masaki Koyama, Kosei Nei, Akihisa Shimomura, Suguru Hondo, Toru Hasegawa
  • Patent number: 9431435
    Abstract: To improve the electrical characteristics of a semiconductor device including an oxide semiconductor, and to provide a highly reliable semiconductor device with a small variation in electrical characteristics. The semiconductor device includes a first insulating film, a first barrier film over the first insulating film, a second insulating film over the first barrier film, and a first transistor including a first oxide semiconductor film over the second insulating film. The amount of hydrogen molecules released from the first insulating film at a given temperature higher than or equal to 400° C., which is measured by thermal desorption spectroscopy, is less than or equal to 130% of the amount of released hydrogen molecules at 300° C. The second insulating film includes a region containing oxygen at a higher proportion than oxygen in the stoichiometric composition.
    Type: Grant
    Filed: October 21, 2014
    Date of Patent: August 30, 2016
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Yoshinori Ando, Hidekazu Miyairi, Naoto Yamade, Asako Higa, Miki Suzuki, Yoshinori Ieda, Yasutaka Suzuki, Kosei Nei, Shunpei Yamazaki
  • Patent number: 9276091
    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: Grant
    Filed: April 16, 2015
    Date of Patent: March 1, 2016
    Assignee: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Suguru Hondo, Akihisa Shimomura, Masaki Koyama, Motomu Kurata, Kazuya Hanaoka, Sho Nagamatsu, Kosei Nei, Toru Hasegawa
  • Publication number: 20150221754
    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: April 16, 2015
    Publication date: August 6, 2015
    Inventors: Suguru HONDO, Akihisa SHIMOMURA, Masaki KOYAMA, Motomu KURATA, Kazuya HANAOKA, Sho NAGAMATSU, Kosei NEI, Toru HASEGAWA
  • Patent number: 9048265
    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: Grant
    Filed: May 20, 2013
    Date of Patent: June 2, 2015
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Suguru Hondo, Akihisa Shimomura, Masaki Koyama, Motomu Kurata, Kazuya Hanaoka, Sho Nagamatsu, Kosei Nei, Toru Hasegawa
  • Publication number: 20150108475
    Abstract: To improve the electrical characteristics of a semiconductor device including an oxide semiconductor, and to provide a highly reliable semiconductor device with a small variation in electrical characteristics. The semiconductor device includes a first insulating film, a first barrier film over the first insulating film, a second insulating film over the first barrier film, and a first transistor including a first oxide semiconductor film over the second insulating film. The amount of hydrogen molecules released from the first insulating film at a given temperature higher than or equal to 400° C., which is measured by thermal desorption spectroscopy, is less than or equal to 130% of the amount of released hydrogen molecules at 300° C. The second insulating film includes a region containing oxygen at a higher proportion than oxygen in the stoichiometric composition.
    Type: Application
    Filed: October 21, 2014
    Publication date: April 23, 2015
    Inventors: Yoshinori Ando, Hidekazu Miyairi, Naoto Yamade, Asako Higa, Miki Suzuki, Yoshinori Ieda, Yasutaka Suzuki, Kosei Nei, Shunpei Yamazaki
  • 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
  • Patent number: 8530336
    Abstract: Defects in a semiconductor substrate are reduced. A semiconductor substrate with fewer defects is manufactured with high yield. Further, a semiconductor device is manufactured with high yield. A semiconductor layer is formed over a supporting substrate with an oxide insulating layer interposed therebetween, adhesiveness between the supporting substrate and the oxide insulating layer in an edge portion of the semiconductor layer is increased, an insulating layer over a surface of the semiconductor layer is removed, and the semiconductor layer is irradiated with laser light, so that a planarized semiconductor layer is obtained. For increasing the adhesiveness between the supporting substrate and the oxide insulating layer in the edge portion of the semiconductor layer, laser light irradiation is performed from the surface of the semiconductor layer.
    Type: Grant
    Filed: November 9, 2011
    Date of Patent: September 10, 2013
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Kosei Nei, Akihisa Shimomura
  • Patent number: 8383487
    Abstract: Forming an insulating film on a surface of the single crystal semiconductor substrate, forming a fragile region in the single crystal semiconductor substrate by irradiating the single crystal semiconductor substrate with an ion beam through the insulating film, forming a bonding layer over the insulating film, bonding a supporting substrate to the single crystal semiconductor substrate by interposing the bonding layer between the supporting substrate and the single crystal semiconductor substrate, dividing the single crystal semiconductor substrate at the fragile region to separate the single crystal semiconductor substrate into a single crystal semiconductor layer attached to the supporting substrate, performing first dry etching treatment on a part of the fragile region remaining on the single crystal semiconductor layer, performing second dry etching treatment on a surface of the single crystal semiconductor layer subjected to the first etching treatment, and irradiating the single crystal semiconductor la
    Type: Grant
    Filed: August 4, 2011
    Date of Patent: February 26, 2013
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Hideomi Suzawa, Shinya Sasagawa, Akihisa Shimomura, Junpei Momo, Motomu Kurata, Taiga Muraoka, Kosei Nei
  • 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
  • Publication number: 20120211862
    Abstract: The method for manufacturing an SOI substrate includes the following steps: forming an insulating film on a semiconductor substrate; exposing the semiconductor substrate to accelerated ions so that an embrittlement region is formed in the semiconductor substrate; bonding the semiconductor substrate to a base substrate with the insulating film interposed therebetween; separating the semiconductor substrate along the embrittlement region so that a semiconductor film is provided over the base substrate with the insulating film interposed therebetween; and forming a mask over the semiconductor film to etch part of the semiconductor film and part of the insulating film so that the periphery of the semiconductor film is on the inner side than the periphery of the insulating film.
    Type: Application
    Filed: February 14, 2012
    Publication date: August 23, 2012
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Masaharu NAGAI, Hideto OHNUMA, Kosei NEI
  • 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
  • Publication number: 20120122298
    Abstract: Defects in a semiconductor substrate are reduced. A semiconductor substrate with fewer defects is manufactured with high yield. Further, a semiconductor device is manufactured with high yield. A semiconductor layer is formed over a supporting substrate with an oxide insulating layer interposed therebetween, adhesiveness between the supporting substrate and the oxide insulating layer in an edge portion of the semiconductor layer is increased, an insulating layer over a surface of the semiconductor layer is removed, and the semiconductor layer is irradiated with laser light, so that a planarized semiconductor layer is obtained. For increasing the adhesiveness between the supporting substrate and the oxide insulating layer in the edge portion of the semiconductor layer, laser light irradiation is performed from the surface of the semiconductor layer.
    Type: Application
    Filed: November 9, 2011
    Publication date: May 17, 2012
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Kosei NEI, Akihisa SHIMOMURA
  • Patent number: 8093112
    Abstract: A method for manufacturing display devices including thin film transistors with high reliability in a high yield is provided. A gate insulating film is formed over a gate electrode; a microcrystalline semiconductor is formed over the gate insulating film; the microcrystalline semiconductor film is irradiated with a laser beam from the surface side thereof, whereby the crystallinity of the microcrystalline semiconductor film is improved. Then, a thin film transistor is formed using the microcrystalline semiconductor film whose crystallinity is improved. Further, a display device including the thin film transistor is manufactured.
    Type: Grant
    Filed: July 15, 2008
    Date of Patent: January 10, 2012
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Hidekazu Miyairi, Yasuhiro Jinbo, Kosei Nei
  • Publication number: 20110287605
    Abstract: Forming an insulating film on a surface of the single crystal semiconductor substrate, forming a fragile region in the single crystal semiconductor substrate by irradiating the single crystal semiconductor substrate with an ion beam through the insulating film, forming a bonding layer over the insulating film, bonding a supporting substrate to the single crystal semiconductor substrate by interposing the bonding layer between the supporting substrate and the single crystal semiconductor substrate, dividing the single crystal semiconductor substrate at the fragile region to separate the single crystal semiconductor substrate into a single crystal semiconductor layer attached to the supporting substrate, performing first dry etching treatment on a part of the fragile region remaining on the single crystal semiconductor layer, performing second dry etching treatment on a surface of the single crystal semiconductor layer subjected to the first etching treatment, and irradiating the single crystal semiconductor la
    Type: Application
    Filed: August 4, 2011
    Publication date: November 24, 2011
    Applicant: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Hideomi SUZAWA, Shinya SASAGAWA, Akihisa SHIMOMURA, Junpei MOMO, Motomu KURATA, Taiga MURAOKA, Kosei NEI
  • Patent number: 8048773
    Abstract: A single crystal semiconductor separated from a single crystal semiconductor substrate is formed partly over a supporting substrate with a buffer layer provided therebetween. The single crystal semiconductor is separated from the single crystal semiconductor substrate by irradiation with accelerated ions, formation of a fragile layer by the ion irradiation, and heat treatment. A non-single crystal semiconductor layer is formed over the single crystal semiconductor and irradiated with a laser beam to be crystallized, whereby an SOI substrate is manufactured.
    Type: Grant
    Filed: March 23, 2010
    Date of Patent: November 1, 2011
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Shunpei Yamazaki, Masaki Koyama, Kosei Noda, Kenichiro Makino, Hideto Ohnuma, Kosei Nei