Patents by Inventor Akihisa Shimomura

Akihisa Shimomura 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: 9698274
    Abstract: A transistor with stable electrical characteristics or a transistor with normally-off electrical characteristics. The transistor is a semiconductor device including a conductor, a semiconductor, a first insulator, and a second insulator. The semiconductor is over the first insulator. The conductor is over the semiconductor. The second insulator is between the conductor and the semiconductor. The first insulator includes fluorine and hydrogen. The fluorine concentration of the first insulator is higher than the hydrogen concentration of the first insulator.
    Type: Grant
    Filed: October 15, 2015
    Date of Patent: July 4, 2017
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Shunpei Yamazaki, Akihisa Shimomura, Yasumasa Yamane, Naoto Yamade, Tetsuhiro Tanaka
  • Patent number: 9698277
    Abstract: A transistor with stable electrical characteristics is provided. The transistor includes a first insulator over a substrate; first to third oxide insulators over the first insulator; a second insulator over the third oxide insulator; a first conductor over the second insulator; and a third insulator over the first conductor. An energy level of a conduction band minimum of each of the first and second oxide insulators is closer to a vacuum level than that of the oxide semiconductor is. An energy level of a conduction band minimum of the third oxide insulator is closer to the vacuum level than that of the second oxide insulator is. The first insulator contains oxygen. The number of oxygen molecules released from the first insulator measured by thermal desorption spectroscopy is greater than or equal to 1E14 molecules/cm2 and less than or equal to 1E16 molecules/cm2.
    Type: Grant
    Filed: December 9, 2015
    Date of Patent: July 4, 2017
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Shunpei Yamazaki, Tetsuhiro Tanaka, Akihisa Shimomura, Yasumasa Yamane, Ryo Tokumaru, Yuhei Sato, Kazuhiro Tsutsui
  • Patent number: 9666755
    Abstract: Methods of manufacturing a sealed body and a light-emitting device with high airtightness in which generation of a crack in a substrate and a frit glass in an overlap region where laser light irradiation is started and ended is prevented are provided. A high-reflectivity region having high reflectivity with respect to laser light and a low-reflectivity region having lower reflectivity than the high-reflectivity region are provided in a region which overlaps with the frit glass and is over a substrate facing a substrate on which the frit glass is formed. When scanning with laser light is started from the low-reflectivity region, a crack is less likely to be generated in the frit glass.
    Type: Grant
    Filed: November 28, 2012
    Date of Patent: May 30, 2017
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventor: Akihisa Shimomura
  • Publication number: 20170141233
    Abstract: Favorable electrical characteristics are given to a semiconductor device. Furthermore, a semiconductor device having high reliability is provided. One embodiment of the present invention is an oxide semiconductor film having a plurality of electron diffraction patterns which are observed in such a manner that a surface where the oxide semiconductor film is formed is irradiated with an electron beam having a probe diameter whose half-width is 1 nm. The plurality of electron diffraction patterns include 50 or more electron diffraction patterns which are observed in different areas, the sum of the percentage of first electron diffraction patterns and the percentage of second electron diffraction patterns accounts for 100%, the first electron diffraction patterns account for 90% or more, the first electron diffraction pattern includes observed points which indicates that a c-axis is oriented in a direction substantially perpendicular to the surface where the oxide semiconductor film is formed.
    Type: Application
    Filed: January 27, 2017
    Publication date: May 18, 2017
    Inventors: Akihisa SHIMOMURA, Yasumasa YAMANE, Yuhei SATO, Takahisa ISHIYAMA, Kenichi OKAZAKI, Chiho KAWANABE, Masashi OOTA, Noritaka ISHIHARA
  • Patent number: 9653613
    Abstract: Provided is a transistor with stable electrical characteristics. Provided is a semiconductor device including an oxide semiconductor over a substrate, a first conductor in contact with a top surface of the oxide semiconductor, a second conductor in contact with the top surface of the oxide semiconductor, a first insulator over the first and second conductors and in contact with the top surface of the oxide semiconductor, a second insulator over the first insulator, a third conductor over the second insulator, and a third insulator over the third conductor. The third conductor overlaps with the first conductor with the first and second insulators positioned therebetween, and overlaps with the second conductor with the first and second insulators positioned therebetween. The first insulator contains oxygen. The second insulator transmits less oxygen than the first insulator. The third insulator transmits less oxygen than the first insulator.
    Type: Grant
    Filed: February 19, 2016
    Date of Patent: May 16, 2017
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Shunpei Yamazaki, Tetsuhiro Tanaka, Akihisa Shimomura, Ryo Tokumaru, Yasumasa Yamane, Yuhei Sato, Naoki Okuno, Motoki Nakashima
  • Publication number: 20170062214
    Abstract: The present invention is characterized in that by laser beam being slantly incident to the convex lens, an aberration such as astigmatism or the like is occurred, and the shape of the laser beam is made linear on the irradiation surface or in its neighborhood. Since the present invention has a very simple configuration, the optical adjustment is easier, and the device becomes compact in size. Furthermore, since the beam is slantly incident with respect to the irradiated body, the return beam can be prevented.
    Type: Application
    Filed: November 14, 2016
    Publication date: March 2, 2017
    Inventors: Koichiro TANAKA, Hidekazu MIYAIRI, Aiko SHIGA, Akihisa SHIMOMURA, Atsuo ISOBE
  • Publication number: 20170062619
    Abstract: A minute transistor is provided. A transistor with low parasitic capacitance is provided. A transistor having high frequency characteristics is provided. A transistor having a high on-state current is provided. A semiconductor device including the transistor is provided. A semiconductor device having a high degree of integration is provided. A semiconductor device including an oxide semiconductor; a second insulator; a second conductor; a third conductor; a fourth conductor; a fifth conductor; a first conductor and a first insulator embedded in an opening portion formed in the second insulator, the second conductor, the third conductor, the fourth conductor, and the fifth conductor; a region where a side surface and a bottom surface of the second conductor are in contact with the fourth conductor; and a region where a side surface and a bottom surface of the third conductor are in contact with the fifth conductor.
    Type: Application
    Filed: August 12, 2016
    Publication date: March 2, 2017
    Inventors: Shinya SASAGAWA, Takashi HAMADA, Akihisa SHIMOMURA, Satoru OKAMOTO, Katsuaki TOCHIBAYASHI
  • Publication number: 20170062620
    Abstract: A novel oxide semiconductor is provided. An oxide semiconductor contains In, an element M (M represents Al, Ga, Y, or Sn), and Zn. The oxide semiconductor has little characteristics variation and structure change and has high electron mobility in the case where the atomic ratio of In to M and Zn in the oxide semiconductor ranges from 4:2:3 to 4:2:4.1 or is a neighborhood thereof.
    Type: Application
    Filed: August 23, 2016
    Publication date: March 2, 2017
    Inventors: Shunpei YAMAZAKI, Masashi TSUBUKU, Masashi OOTA, Akihisa SHIMOMURA, Yasumasa YAMANE
  • Patent number: 9577107
    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: Grant
    Filed: March 13, 2014
    Date of Patent: February 21, 2017
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Akihisa Shimomura, Takahisa Ishiyama, Masaki Koyama, Erumu Kikuchi, Takuya Hirohashi, Masashi Oota
  • Publication number: 20170033111
    Abstract: A novel semiconductor device or memory device is provided. Alternatively, a semiconductor device or memory device in which storage capacity per unit area is large is provided. The semiconductor device includes a sense amplifier provided to a semiconductor substrate and a memory cell provided over the sense amplifier. The sense amplifier includes a first transistor. The memory cell includes a capacitor over the semiconductor substrate, a second transistor provided over the capacitor, a conductor, and a groove portion. The capacitor includes a first electrode and a second electrode. The first electrode is formed along the groove portion. The second electrode has a region facing the first electrode in the groove portion. The second transistor includes an oxide semiconductor. One of a source and a drain of the second transistor is electrically connected to the second electrode through the conductor.
    Type: Application
    Filed: July 27, 2016
    Publication date: February 2, 2017
    Applicant: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Shunpei YAMAZAKI, Kiyoshi KATO, Hidekazu MIYAIRI, Akihisa SHIMOMURA, Atsushi HIROSE
  • Patent number: 9559174
    Abstract: Favorable electrical characteristics are given to a semiconductor device. Furthermore, a semiconductor device having high reliability is provided. One embodiment of the present invention is an oxide semiconductor film having a plurality of electron diffraction patterns which are observed in such a manner that a surface where the oxide semiconductor film is formed is irradiated with an electron beam having a probe diameter whose half-width is 1 nm. The plurality of electron diffraction patterns include 50 or more electron diffraction patterns which are observed in different areas, the sum of the percentage of first electron diffraction patterns and the percentage of second electron diffraction patterns accounts for 100%, the first electron diffraction patterns account for 90% or more, the first electron diffraction pattern includes observed points which indicates that a c-axis is oriented in a direction substantially perpendicular to the surface where the oxide semiconductor film is formed.
    Type: Grant
    Filed: March 14, 2016
    Date of Patent: January 31, 2017
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Akihisa Shimomura, Yasumasa Yamane, Yuhei Sato, Takahisa Ishiyama, Kenichi Okazaki, Chiho Kawanabe, Masashi Oota, Noritaka Ishihara
  • Publication number: 20170025633
    Abstract: A method for manufacturing a sealed structure in which few cracks are generated is provided. Scan with the laser beam is performed so that there is no difference in an irradiation period between the middle portion and the perimeter portion of the glass layer and so that the scanning direction is substantially parallel to the direction in which solidification of the glass layer after melting proceeds. More specifically, in a region where the beam spot is overlapped with the glass layer, scan is performed with a laser beam having a beam spot shape whose width in a scanning direction is substantially uniform. Further, as a laser beam with which the glass layer is irradiated, a laser beam (a linear laser beam) having a linear beam spot shape with a major axis and a minor axis which is orthogonal to the major axis.
    Type: Application
    Filed: October 7, 2016
    Publication date: January 26, 2017
    Applicant: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Hidekazu Miyairi, Akihisa Shimomura
  • Publication number: 20170018631
    Abstract: A change in electrical characteristics is suppressed and reliability in a semiconductor device using a transistor including an oxide semiconductor is improved. The semiconductor device includes an oxide semiconductor film over an insulating surface, an antioxidant film over the insulating surface and the oxide semiconductor film, a pair of electrodes in contact with the antioxidant film, a gate insulating film over the pair of electrodes, and a gate electrode which is over the gate insulating film and overlaps with the oxide semiconductor film. In the antioxidant film, a width of a region overlapping with the pair of electrodes is longer than a width of a region not overlapping with the pair of electrodes.
    Type: Application
    Filed: September 27, 2016
    Publication date: January 19, 2017
    Inventors: Shunpei YAMAZAKI, Akihisa SHIMOMURA, Yasumasa YAMANE, Yuhei SATO, Tetsuhiro TANAKA, Masashi TSUBUKU, Toshihiko TAKEUCHI, Ryo TOKUMARU, Mitsuhiro ICHIJO, Satoshi TORIUMI, Takashi OHTSUKI, Toshiya ENDO
  • Publication number: 20170018655
    Abstract: A transistor with favorable electrical characteristics is provided. One embodiment of the present invention is a semiconductor device including a semiconductor, a first insulator in contact with the semiconductor, a first conductor in contact with the first insulator and overlapping with the semiconductor with the first insulator positioned between the semiconductor and the first conductor, and a second conductor and a third conductor, which are in contact with the semiconductor. One or more of the first to third conductors include a region containing tungsten and one or more elements selected from silicon, carbon, germanium, tin, aluminum, and nickel.
    Type: Application
    Filed: July 7, 2016
    Publication date: January 19, 2017
    Inventors: Yutaka OKAZAKI, Akihisa SHIMOMURA, Naoto YAMADE, Tomoya TAKESHITA, Tetsuhiro TANAKA
  • 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: 9478664
    Abstract: A change in electrical characteristics is suppressed and reliability in a semiconductor device using a transistor including an oxide semiconductor is improved. The semiconductor device includes an oxide semiconductor film over an insulating surface, an antioxidant film over the insulating surface and the oxide semiconductor film, a pair of electrodes in contact with the antioxidant film, a gate insulating film over the pair of electrodes, and a gate electrode which is over the gate insulating film and overlaps with the oxide semiconductor film. In the antioxidant film, a width of a region overlapping with the pair of electrodes is longer than a width of a region not overlapping with the pair of electrodes.
    Type: Grant
    Filed: December 18, 2014
    Date of Patent: October 25, 2016
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Shunpei Yamazaki, Akihisa Shimomura, Yasumasa Yamane, Yuhei Sato, Tetsuhiro Tanaka, Masashi Tsubuku, Toshihiko Takeuchi, Ryo Tokumaru, Mitsuhiro Ichijo, Satoshi Toriumi, Takashi Ohtsuki, Toshiya Endo
  • Publication number: 20160308060
    Abstract: A transistor with stable electrical characteristics. A semiconductor device includes a first insulator over a substrate, a second insulator over the first insulator, an oxide semiconductor in contact with at least part of a top surface of the second insulator, a third insulator in contact with at least part of a top surface of the oxide semiconductor, a first conductor and a second conductor electrically connected to the oxide semiconductor, a fourth insulator over the third insulator, a third conductor which is over the fourth insulator and at least part of which is between the first conductor and the second conductor, and a fifth insulator over the third conductor. The first insulator contains a halogen element.
    Type: Application
    Filed: April 7, 2016
    Publication date: October 20, 2016
    Inventors: Tetsuhiro TANAKA, Mitsuhiro ICHIJO, Toshiya ENDO, Akihisa SHIMOMURA, Yuji EGI, Sachiaki TEZUKA, Shunpei YAMAZAKI
  • Patent number: 9472776
    Abstract: A method for manufacturing a sealed structure in which few cracks are generated is provided. Scan with the laser beam is performed so that there is no difference in an irradiation period between the middle portion and the perimeter portion of the glass layer and so that the scanning direction is substantially parallel to the direction in which solidification of the glass layer after melting proceeds. More specifically, in a region where the beam spot is overlapped with the glass layer, scan is performed with a laser beam having a beam spot shape whose width in a scanning direction is substantially uniform. Further, as a laser beam with which the glass layer is irradiated, a laser beam (a linear laser beam) having a linear beam spot shape with a major axis and a minor axis which is orthogonal to the major axis.
    Type: Grant
    Filed: October 4, 2012
    Date of Patent: October 18, 2016
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Hidekazu Miyairi, Akihisa Shimomura
  • Patent number: 9466725
    Abstract: A miniaturized transistor having high electrical characteristics can be provided with high yield. High performance, high reliability, and high productivity of a semiconductor device including the transistor can be achieved. The semiconductor device includes a gate electrode over an insulating surface; a base insulating film which is over the insulating surface and from which the gate electrode protrudes; a gate insulating film over the base insulating film and the gate electrode; an oxide semiconductor film over the gate insulating film; and a source electrode and a drain electrode in contact with an oxide semiconductor film. The thickness of the oxide semiconductor film is smaller than the difference between the thickness of the gate electrode and the thickness of the base insulating film.
    Type: Grant
    Filed: January 16, 2014
    Date of Patent: October 11, 2016
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventor: Akihisa Shimomura
  • Publication number: 20160293768
    Abstract: Disclosed is a semiconductor device including two oxide semiconductor layers, where one of the oxide semiconductor layers has an n-doped region while the other of the oxide semiconductor layers is substantially i-type. The semiconductor device includes the two oxide semiconductor layers sandwiched between a pair of oxide layers which have a common element included in any of the two oxide semiconductor layers. A double-well structure is formed in a region including the two oxide semiconductor layers and the pair of oxide layers, leading to the formation of a channel formation region in the n-doped region. This structure allows the channel formation region to be surrounded by an i-type oxide semiconductor, which contributes to the production of a semiconductor device that is capable of feeding enormous current.
    Type: Application
    Filed: June 16, 2016
    Publication date: October 6, 2016
    Inventors: Shunpei YAMAZAKI, Hideomi SUZAWA, Akihisa SHIMOMURA, Tetsuhiro TANAKA, Sachiaki TEZUKA