Patents by Inventor Chiho Kokubo

Chiho Kokubo 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: 20210118916
    Abstract: A semiconductor device production system using a laser crystallization method is provided which can avoid forming grain boundaries in a channel formulation region of a TFT, thereby preventing grain boundaries rom lowering the mobility of the TFT greatly, from lowering ON current, and from increasing OFF current. Rectangular or stripe pattern depression and projection portions are formed on an insulating film. A semiconductor film is formed on the insulating film. The semiconductor film is irradiated with continuous wave laser light by running the laser light along the stripe pattern depression and projection portions of the insulating film or along the major or minor axis direction of the rectangle. Although continuous wave laser light is most preferred among laser light, it is also possible to use pulse oscillation laser light in irradiating the semiconductor film.
    Type: Application
    Filed: December 24, 2020
    Publication date: April 22, 2021
    Inventors: Atsuo ISOBE, Shunpei YAMAZAKI, Koji DAIRIKI, Hiroshi SHIBATA, Chiho KOKUBO, Tatsuya ARAO, Masahiko HAYAKAWA, Hidekazu MIYAIRI, Akihisa SHIMOMURA, Koichiro TANAKA, Mai AKIBA
  • Patent number: 10879272
    Abstract: A semiconductor device production system using a laser crystallization method is provided which can avoid forming grain boundaries in a channel formation region of a TFT, thereby preventing grain boundaries from lowering the mobility of the TFT greatly, from lowering ON current, and from increasing OFF current. Rectangular or stripe pattern depression and projection portions are formed on an insulating film. A semiconductor film is formed on the insulating film. The semiconductor film is irradiated with continuous wave laser light by running the laser light along the stripe pattern depression and projection portions of the insulating film or along the major or minor axis direction of the rectangle. Although continuous wave laser light is most preferred among laser light, it is also possible to use pulse oscillation laser light in irradiating the semiconductor film.
    Type: Grant
    Filed: December 23, 2019
    Date of Patent: December 29, 2020
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Atsuo Isobe, Shunpei Yamazaki, Koji Dairiki, Hiroshi Shibata, Chiho Kokubo, Tatsuya Arao, Masahiko Hayakawa, Hidekazu Miyairi, Akihisa Shimomura, Koichiro Tanaka, Mai Akiba
  • Publication number: 20200135770
    Abstract: A semiconductor device production system using a laser crystallization method is provided which can avoid forming grain boundaries in a channel formation region of a TFT, thereby preventing grain boundaries from lowering the mobility of the TFT greatly, from lowering ON current, and from increasing OFF current. Rectangular or stripe pattern depression and projection portions are formed on an insulating film. A semiconductor film is formed on the insulating film. The semiconductor film is irradiated with continuous wave laser light by running the laser light along the stripe pattern depression and projection portions of the insulating film or along the major or minor axis direction of the rectangle. Although continuous wave laser light is most preferred among laser light, it is also possible to use pulse oscillation laser light in irradiating the semiconductor film.
    Type: Application
    Filed: December 23, 2019
    Publication date: April 30, 2020
    Inventors: Atsuo ISOBE, Shunpei YAMAZAKI, Koji DAIRIKI, Hiroshi SHIBATA, Chiho KOKUBO, Tatsuya ARAO, Masahiko HAYAKAWA, Hidekazu MIYAIRI, Akihisa SHIMOMURA, Koichiro TANAKA, Mai AKIBA
  • Patent number: 10515983
    Abstract: A semiconductor device production system using a laser crystallization method is provided which can avoid forming grain boundaries in a channel formation region of a TFT, thereby preventing grain boundaries from lowering the mobility of the TFT greatly, from lowering ON current, and from increasing OFF current. Rectangular or stripe pattern depression and projection portions are formed on an insulating film. A semiconductor film is formed on the insulating film. The semiconductor film is irradiated with continuous wave laser light by running the laser light along the stripe pattern depression and projection portions of the insulating film or along the major or minor axis direction of the rectangle. Although continuous wave laser light is most preferred among laser light, it is also possible to use pulse oscillation laser light in irradiating the semiconductor film.
    Type: Grant
    Filed: July 18, 2019
    Date of Patent: December 24, 2019
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Atsuo Isobe, Shunpei Yamazaki, Koji Dairiki, Hiroshi Shibata, Chiho Kokubo, Tatsuya Arao, Masahiko Hayakawa, Hidekazu Miyairi, Akihisa Shimomura, Koichiro Tanaka, Mai Akiba
  • Publication number: 20190341404
    Abstract: A semiconductor device production system using a laser crystallization method is provided which can avoid forming grain boundaries in a channel formation region of a TFT, thereby preventing grain boundaries from lowering the mobility of the TFT greatly, from lowering ON current, and from increasing OFF current. Rectangular or stripe pattern depression and projection portions are formed on an insulating film. A semiconductor film is formed on the insulating film. The semiconductor film is irradiated with continuous wave laser light by running the laser light along the stripe pattern depression and projection portions of the insulating film or along the major or minor axis direction of the rectangle. Although continuous wave laser light is most preferred among laser light, it is also possible to use pulse oscillation laser light in irradiating the semiconductor film.
    Type: Application
    Filed: July 18, 2019
    Publication date: November 7, 2019
    Inventors: Atsuo ISOBE, Shunpei YAMAZAKI, Koji DAIRIKI, Hiroshi SHIBATA, Chiho KOKUBO, Tatsuya ARAO, Masahiko HAYAKAWA, Hidekazu MIYAIRI, Akihisa SHIMOMURA, Koichiro TANAKA, Mai AKIBA
  • Patent number: 10361222
    Abstract: A semiconductor device production system using a laser crystallization method is provided which can avoid forming grain boundaries in a channel formulation region of a TFT, thereby preventing grain boundaries from lowering the mobility of the TFT greatly, from lowering ON current, and from increasing OFF current. Rectangular or stripe pattern depression and projection portions are formed on an insulating film. A semiconductor film is formed on the insulating film. The semiconductor film is irradiated with continuous wave laser light by running the laser light along the stripe pattern depression and projection portions of the insulating film or along the major or minor axis direction of the rectangle. Although continuous wave laser light is most preferred among laser light, it is also possible to use pulse oscillation laser light in irradiating the semiconductor film.
    Type: Grant
    Filed: February 15, 2018
    Date of Patent: July 23, 2019
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Atsuo Isobe, Shunpei Yamazaki, Koji Dairiki, Hiroshi Shibata, Chiho Kokubo, Tatsuya Arao, Masahiko Hayakawa, Hidekazu Miyairi, Akihisa Shimomura, Koichiro Tanaka, Mai Akiba
  • Publication number: 20180190677
    Abstract: A semiconductor device production system using a laser crystallization method is provided which can avoid forming grain boundaries in a channel formulation region of a TFT, thereby preventing grain boundaries from lowering the mobility of the TFT greatly, from lowering ON current, and from increasing OFF current. Rectangular or stripe pattern depression and projection portions are formed on an insulating film. A semiconductor film is formed on the insulating film. The semiconductor film is irradiated with continuous wave laser light by running the laser light along the stripe pattern depression and projection portions of the insulating film or along the major or minor axis direction of the rectangle. Although continuous wave laser light is most preferred among laser light, it is also possible to use pulse oscillation laser light in irradiating the semiconductor film.
    Type: Application
    Filed: February 15, 2018
    Publication date: July 5, 2018
    Inventors: Atsuo ISOBE, Shunpei YAMAZAKI, Koji DAIRIKI, Hiroshi SHIBATA, Chiho KOKUBO, Tatsuya ARAO, Masahiko HAYAKAWA, Hidekazu MIYAIRI, Akihisa SHIMOMURA, Koichiro TANAKA, Mai AKIBA
  • Patent number: 9899419
    Abstract: A semiconductor device production system using a laser crystallization method is provided which can avoid forming grain boundaries in a channel formation region of a TFT, thereby preventing grain boundaries from lowering the mobility of the TFT greatly, from lowering ON current, and from increasing OFF current. Rectangular or stripe pattern depression and projection portions are formed on an insulating film. A semiconductor film is formed on the insulating film. The semiconductor film is irradiated with continuous wave laser light by running the laser light along the stripe pattern depression and projection portions of the insulating film or along the major or minor axis direction of the rectangle. Although continuous wave laser light is most preferred among laser light, it is also possible to use pulse oscillation laser light in irradiating the semiconductor film.
    Type: Grant
    Filed: October 27, 2015
    Date of Patent: February 20, 2018
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Atsuo Isobe, Shunpei Yamazaki, Koji Dairiki, Hiroshi Shibata, Chiho Kokubo, Tatsuya Arao, Masahiko Hayakawa, Hidekazu Miyairi, Akihisa Shimomura, Koichiro Tanaka, Mai Akiba
  • Publication number: 20170025546
    Abstract: A first shape of semiconductor region having on its one side a plurality of sharp convex top-end portions is formed first and a continuous wave laser beam is used for radiation from the above region so as to crystallize the first shape of semiconductor region. A continuous wave laser beam condensed in one or plural lines is used for the laser beam. The first shape of semiconductor region is etched to form a second shape of semiconductor region in which a channel forming region and a source and drain region are formed. The second shape of semiconductor region is disposed so that a channel forming range would be formed on respective crystal regions extending from the plurality of convex end portions. A semiconductor region adjacent to the channel forming region is eliminated.
    Type: Application
    Filed: October 5, 2016
    Publication date: January 26, 2017
    Inventors: Chiho KOKUBO, Aiko SHIGA, Shunpei YAMAZAKI, Hidekazu MIYAIRI, Koji DAIRIKI, Koichiro TANAKA
  • Publication number: 20160111451
    Abstract: A semiconductor device production system using a laser crystallization method is provided which can avoid forming grain boundaries in a channel formation region of a TFT, thereby preventing grain boundaries from lowering the mobility of the TFT greatly, from lowering ON current, and from increasing OFF current. Rectangular or stripe pattern depression and projection portions are formed on an insulating film. A semiconductor film is formed on the insulating film. The semiconductor film is irradiated with continuous wave laser light by running the laser light along the stripe pattern depression and projection portions of the insulating film or along the major or minor axis direction of the rectangle. Although continuous wave laser light is most preferred among laser light, it is also possible to use pulse oscillation laser light in irradiating the semiconductor film.
    Type: Application
    Filed: October 27, 2015
    Publication date: April 21, 2016
    Inventors: Atsuo ISOBE, Shunpei YAMAZAKI, Koji DAIRIKI, Hiroshi SHIBATA, Chiho KOKUBO, Tatsuya ARAO, Masahiko HAYAKAWA, Hidekazu MIYAIRI, Akihisa SHIMOMURA, Koichiro TANAKA, Mai AKIBA
  • Patent number: 9178069
    Abstract: A semiconductor device production system using a laser crystallization method is provided which can avoid forming grain boundaries in a channel formation region of a TFT, thereby preventing grain boundaries from lowering the mobility of the TFT greatly, from lowering ON current, and from increasing OFF current. Rectangular or stripe pattern depression and projection portions are formed on an insulating film. A semiconductor film is formed on the insulating film. The semiconductor film is irradiated with continuous wave laser light by running the laser light along the stripe pattern depression and projection portions of the insulating film or along the major or minor axis direction of the rectangle. Although continuous wave laser light is most preferred among laser light, it is also possible to use pulse oscillation laser light in irradiating the semiconductor film.
    Type: Grant
    Filed: July 31, 2009
    Date of Patent: November 3, 2015
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Atsuo Isobe, Shunpei Yamazaki, Koji Dairiki, Hiroshi Shibata, Chiho Kokubo, Tatsuya Arao, Masahiko Hayakawa, Hidekazu Miyairi, Akihisa Shimomura, Koichiro Tanaka, Mai Akiba
  • Patent number: 8314426
    Abstract: There is disclosed a semiconductor device and a method of fabricating the semiconductor device in which a heat treatment time required for crystal growth is shortened and a process is simplified. Two catalytic element introduction regions are arranged at both sides of one active layer and crystallization is made. A boundary portion where crystal growth from one catalytic element introduction region meets crystal growth from the other catalytic element introduction region is formed in a region which becomes a source region or drain region.
    Type: Grant
    Filed: September 15, 2011
    Date of Patent: November 20, 2012
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Chiho Kokubo, Hirokazu Yamagata, Shunpei Yamazaki
  • Publication number: 20120097963
    Abstract: A first shape of semiconductor region having on its one side a plurality of sharp convex top-end portions is formed first and a continuous wave laser beam is used for radiation from the above region so as to crystallize the first shape of semiconductor region. A continuous wave laser beam condensed in one or plural lines is used for the laser beam. The first shape of semiconductor region is etched to form a second shape of semiconductor region in which a channel forming region and a source and drain region are formed. The second shape of semiconductor region is disposed so that a channel foaming range would be formed on respective crystal regions extending from the plurality of convex end portions. A semiconductor region adjacent to the channel forming region is eliminated.
    Type: Application
    Filed: December 30, 2011
    Publication date: April 26, 2012
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Chiho KOKUBO, Aiko Shiga, Shunpei Yamazaki, Hidekazu Miyairi, Koji Dairiki, Koichiro Tanaka
  • Publication number: 20120062809
    Abstract: There is disclosed a semiconductor device and a method of fabricating the semiconductor device in which a heat treatment time required for crystal growth is shortened and a process is simplified. Two catalytic element introduction regions are arranged at both sides of one active layer and crystallization is made. A boundary portion where crystal growth from one catalytic element introduction region meets crystal growth from the other catalytic element introduction region is formed in a region which becomes a source region or drain region.
    Type: Application
    Filed: September 15, 2011
    Publication date: March 15, 2012
    Applicant: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Chiho KOKUBO, Hirokazu YAMAGATA, Shunpei YAMAZAKI
  • Patent number: 8093593
    Abstract: A first shape of semiconductor region having on its one side a plurality of sharp convex top-end portions is formed first and a continuous wave laser beam is used for radiation from the above region so as to crystallize the first shape of semiconductor region. A continuous wave laser beam condensed in one or plural lines is used for the laser beam. The first shape of semiconductor region is etched to form a second shape of semiconductor region in which a channel forming region and a source and drain region are formed. The second shape of semiconductor region is disposed so that a channel forming range would be formed on respective crystal regions extending from the plurality of convex end portions. A semiconductor region adjacent to the channel forming region is eliminated.
    Type: Grant
    Filed: September 7, 2006
    Date of Patent: January 10, 2012
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Chiho Kokubo, Aiko Shiga, Shunpei Yamazaki, Hidekazu Miyairi, Koji Dairiki, Koichiro Tanaka
  • Patent number: 8026518
    Abstract: There is disclosed a semiconductor device and a method of fabricating the semiconductor device in which a heat treatment time required for crystal growth is shortened and a process is simplified. Two catalytic element introduction regions are arranged at both sides of one active layer and crystallization is made. A boundary portion where crystal growth from one catalytic element introduction region meets crystal growth from the other catalytic element introduction region is formed in a region which becomes a source region or drain region.
    Type: Grant
    Filed: April 7, 2010
    Date of Patent: September 27, 2011
    Assignee: Semiconductor Energy Laboratory Co. Ltd.
    Inventors: Chiho Kokubo, Hirokazu Yamagata, Shunpei Yamazaki
  • Patent number: 7795734
    Abstract: To provide a semiconductor device composed of a semiconductor element or a group of semiconductor elements, in which a crystalline semiconductor film having as few grain boundaries as possible in a channel formation region is formed on an insulating surface, which can operate at high speed, which have high current drive performance, and which are less fluctuated between elements.
    Type: Grant
    Filed: December 11, 2006
    Date of Patent: September 14, 2010
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Atsuo Isobe, Shunpei Yamazaki, Chiho Kokubo, Koichiro Tanaka, Akihisa Shimomura, Tatsuya Arao, Hidekazu Miyairi
  • Publication number: 20100195012
    Abstract: There is disclosed a semiconductor device and a method of fabricating the semiconductor device in which a heat treatment time required for crystal growth is shortened and a process is simplified. Two catalytic element introduction regions are arranged at both sides of one active layer and crystallization is made. A boundary portion where crystal growth from one catalytic element introduction region meets crystal growth from the other catalytic element introduction region is formed in a region which becomes a source region or drain region.
    Type: Application
    Filed: April 7, 2010
    Publication date: August 5, 2010
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Chiho KOKUBO, Hirokazu YAMAGATA, Shunpei YAMAZAKI
  • Patent number: 7749818
    Abstract: An objective is to provide a method of manufacturing a semiconductor device, and a semiconductor device manufactured by using the manufacturing method, in which a laser crystallization method is used that is capable of preventing the formation of grain boundaries in TFT channel formation regions, and is capable of preventing conspicuous drops in TFT mobility, reduction in the ON current, and increases in the OFF current, all due to grain boundaries. Stripe shape or rectangular shape unevenness or opening is formed. Continuous wave laser light is then irradiated to a semiconductor film formed on an insulating film. Note that although it is most preferable to use continuous wave laser light at this point, pulse wave oscillation laser light may also be used.
    Type: Grant
    Filed: January 28, 2003
    Date of Patent: July 6, 2010
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Atsuo Isobe, Shunpei Yamazaki, Chiho Kokubo, Koichiro Tanaka, Akihisa Shimomura, Tatsuya Arao, Hidekazu Miyairi, Mai Akiba
  • Patent number: 7737506
    Abstract: An objective is to provide a method of manufacturing a semiconductor device, and a semiconductor device manufactured by using the manufacturing method, in which a laser crystallization method is used that is capable of preventing the formation of grain boundaries in TFT channel formation regions, and is capable of preventing conspicuous drops in TFT mobility, reduction in the ON current, and increases in the OFF current, all due to grain boundaries. Depressions and projections with stripe shape or rectangular shape are formed. Continuous wave laser light is then irradiated to a semiconductor film formed on an insulating film along the depressions and projections with stripe shape of the insulating film, or along a longitudinal axis direction or a transverse axis direction of the rectangular shape. Note that although it is most preferable to use continuous wave laser light at this point, pulse wave laser light may also be used.
    Type: Grant
    Filed: August 31, 2006
    Date of Patent: June 15, 2010
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Atsuo Isobe, Shunpei Yamazaki, Chiho Kokubo, Koichiro Tanaka, Akihisa Shimomura, Tatsuya Arao, Hidekazu Miyairi, Mai Akiba