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).

  • Publication number: 20150053264
    Abstract: An object is to increase conversion efficiency of a photoelectric conversion device without increase in the manufacturing steps. The photoelectric conversion device includes a first semiconductor layer formed using a single crystal semiconductor having one conductivity type which is formed over a supporting substrate, a buffer layer including a single crystal region and an amorphous region, a second semiconductor layer which includes a single crystal region and an amorphous region and is provided over the butler layer, and a third semiconductor layer having a conductivity type opposite to the one conductivity type, which is provided over the second semiconductor layer. A proportion of the single crystal region is higher than that of the amorphous region on the first semiconductor layer side in the second semiconductor layer, and the proportion of the amorphous region is higher than that of the single crystal region on the third semiconductor layer side.
    Type: Application
    Filed: October 15, 2014
    Publication date: February 26, 2015
    Inventors: Sho KATO, Yoshikazu HIURA, Akihisa SHIMOMURA, Takashi OHTSUKI, Satoshi TORIUMI, Yasuyuki ARAI
  • Publication number: 20150001532
    Abstract: To provide a semiconductor device in which a large current can flow. To provide a semiconductor device which can be driven stably at a high driving voltage. The semiconductor device includes a semiconductor layer, a first electrode and a second electrode electrically connected to the semiconductor layer and apart from each other in a region overlapping with the semiconductor layer, a first gate electrode and a second gate electrode with the semiconductor layer therebetween, a first gate insulating layer between the semiconductor layer and the first gate electrode, and a second gate insulating layer between the semiconductor layer and the second gate electrode. The first gate electrode overlaps with part of the first electrode, the semiconductor layer, and part of the second electrode. The second gate electrode overlaps with the semiconductor layer and part of the first electrode, and does not overlap with the second electrode.
    Type: Application
    Filed: June 24, 2014
    Publication date: January 1, 2015
    Inventors: Shunpei Yamazaki, Yoshiyuki Kobayashi, Daisuke Matsubayashi, Akihisa Shimomura, Daigo Ito
  • Publication number: 20140361320
    Abstract: A highly productive method for sealing substrates with the use of glass frit is provided. A method for sealing substrates with the use of glass frit, which can be used for a substrate provided with a material having low heat resistance, is provided. A highly airtight sealed body which is manufactured by such a method is provided. A light-emitting device having high productivity and high reliability and a manufacturing method thereof are provided. A heat generation layer containing a conductive material which generates heat by induction heating is formed to overlap with a region where a paste including a frit material and a binder is applied. Alternatively, a conductive material which generates heat by induction heating is added to the paste itself. The paste is locally heated by induction heating to remove the binder included in the paste.
    Type: Application
    Filed: August 25, 2014
    Publication date: December 11, 2014
    Inventor: Akihisa Shimomura
  • Patent number: 8895407
    Abstract: A manufacturing method of an SOI substrate which possesses a base substrate having low heat resistance and a very thin semiconductor layer having high planarity is demonstrated. The method includes: implanting hydrogen ions into a semiconductor substrate to form an ion implantation layer; bonding the semiconductor substrate and a base substrate such as a glass substrate, placing a bonding layer therebetween; heating the substrates bonded to each other to separate the semiconductor substrate from the base substrate, leaving a thin semiconductor layer over the base substrate; irradiating the surface of the thin semiconductor layer with laser light to improve the planarity and recover the crystallinity of the thin semiconductor layer; and thinning the thin semiconductor layer. This method allows the formation of an SOI substrate which has a single-crystalline semiconductor layer with a thickness of 100 nm or less over a base substrate.
    Type: Grant
    Filed: September 27, 2010
    Date of Patent: November 25, 2014
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Hidekazu Miyairi, Akihisa Shimomura, Tatsuya Mizoi, Eiji Higa, Yoji Nagano
  • 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
  • Patent number: 8872021
    Abstract: An object is to increase conversion efficiency of a photoelectric conversion device without increase in the manufacturing steps. The photoelectric conversion device includes a first semiconductor layer formed using a single crystal semiconductor having one conductivity type which is formed over a supporting substrate, a buffer layer including a single crystal region and an amorphous region, a second semiconductor layer which includes a single crystal region and an amorphous region and is provided over the buffer layer, and a third semiconductor layer having a conductivity type opposite to the one conductivity type, which is provided over the second semiconductor layer. A proportion of the single crystal region is higher than that of the amorphous region on the first semiconductor layer side in the second semiconductor layer, and the proportion of the amorphous region is higher than that of the single crystal region on the third semiconductor layer side.
    Type: Grant
    Filed: September 23, 2009
    Date of Patent: October 28, 2014
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Sho Kato, Yoshikazu Hiura, Akihisa Shimomura, Takashi Ohtsuki, Satoshi Toriumi, Yasuyuki Arai
  • Patent number: 8867585
    Abstract: The present invention provides a laser oscillator using an electroluminescent material that can enhance directivity of emitted laser light and resistance to a physical impact. The laser oscillator has a first layer including a concave portion, a second layer formed over the first layer to cover the concave portion, and a light emitting element formed over the second layer to overlap the concave portion, wherein the second layer is planarized, an axis of laser light obtained from the light emitting element intersects with a planarized surface of the second layer, the first layer has a curved surface in the concave portion, and a refractive index of the first layer is lower than that of the second layer.
    Type: Grant
    Filed: November 9, 2011
    Date of Patent: October 21, 2014
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Ryoji Nomura, Akihisa Shimomura
  • 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: 8828844
    Abstract: A damaged region is formed by generation of plasma by excitation of a source gas, and by addition of ion species contained in the plasma from one of surfaces of a single crystal semiconductor substrate; an insulating layer is formed over the other surface of the single crystal semiconductor substrate; a supporting substrate is firmly attached to the single crystal semiconductor substrate so as to face the single crystal semiconductor substrate with the insulating layer interposed therebetween; separation is performed at the damaged region into the supporting substrate to which a single crystal semiconductor layer is attached and part of the single crystal semiconductor substrate by heating of the single crystal semiconductor substrate; dry etching is performed on a surface of the single crystal semiconductor layer attached to the supporting substrate; the single crystal semiconductor layer is recrystallized by irradiation of the single crystal semiconductor layer with a laser beam to melt at least part of the
    Type: Grant
    Filed: October 8, 2008
    Date of Patent: September 9, 2014
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Hideto Ohnuma, Tetsuya Kakehata, Akihisa Shimomura, Shinya Sasagawa, Motomu Kurata
  • Publication number: 20140246668
    Abstract: A miniaturized transistor having high electrical characteristics is provided with high yield. In a semiconductor device including the transistor, high performance, high reliability, and high productivity can be achieved. The semiconductor device includes a base insulating film, an oxide semiconductor film with a bottom surface and side surfaces in the base insulating film and a top surface exposed from the base insulating film, a source electrode and a drain electrode over the base insulating film and the oxide semiconductor film, a gate insulating film over the oxide semiconductor film, the source electrode, and the drain electrode, and a gate electrode over the gate insulating film and overlapping the oxide semiconductor film.
    Type: Application
    Filed: February 26, 2014
    Publication date: September 4, 2014
    Applicant: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Akihisa Shimomura, Tomoaki Moriwaka, Daigo Ito
  • Publication number: 20140239293
    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: February 6, 2014
    Publication date: August 28, 2014
    Applicant: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Shunpei YAMAZAKI, Hideomi SUZAWA, Akihisa SHIMOMURA, Tetsuhiro TANAKA, Sachiaki TEZUKA
  • Patent number: 8816336
    Abstract: A highly productive method for sealing substrates with the use of glass frit is provided. A method for sealing substrates with the use of glass frit, which can be used for a substrate provided with a material having low heat resistance, is provided. A highly airtight sealed body which is manufactured by such a method is provided. A light-emitting device having high productivity and high reliability and a manufacturing method thereof are provided. A heat generation layer containing a conductive material which generates heat by induction heating is formed to overlap with a region where a paste including a frit material and a binder is applied. Alternatively, a conductive material which generates heat by induction heating is added to the paste itself. The paste is locally heated by induction heating to remove the binder included in the paste.
    Type: Grant
    Filed: June 14, 2012
    Date of Patent: August 26, 2014
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventor: Akihisa Shimomura
  • Publication number: 20140225103
    Abstract: A highly reliable semiconductor device including an oxide semiconductor is provided. Oxygen is supplied from a base insulating layer provided below an oxide semiconductor layer to a channel formation region, whereby oxygen vacancies which might be generated in the channel formation region are filled. Further, a protective insulating layer containing a small amount of hydrogen and functioning as a barrier layer having a low permeability to oxygen is formed over the gate electrode layer so as to cover side surfaces of an oxide layer and a gate insulating layer that are provided over the oxide semiconductor layer, whereby release of oxygen from the gate insulating layer and/or the oxide layer is prevented and generation of oxygen vacancies in a channel formation region is prevented.
    Type: Application
    Filed: February 6, 2014
    Publication date: August 14, 2014
    Applicant: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Sachiaki TEZUKA, Hideomi SUZAWA, Akihisa SHIMOMURA, Tetsuhiro TANAKA
  • Publication number: 20140225104
    Abstract: An object is to provide a semiconductor device that includes an oxide semiconductor and is suitable for a power device. An object is to provide a semiconductor device in which large current can flow. An object is to provide a highly reliable semiconductor device. A semiconductor device includes an oxide stack in which a first oxide layer, a first oxide semiconductor layer, a second oxide semiconductor layer, and a second oxide layer are stacked and has a structure in which a region that contains an element imparting conductivity and is provided in the first oxide semiconductor layer overlaps an electrode functioning as a source electrode and does not overlap an electrode functioning as a drain electrode.
    Type: Application
    Filed: February 6, 2014
    Publication date: August 14, 2014
    Applicant: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Shunpei YAMAZAKI, Hideomi SUZAWA, Akihisa SHIMOMURA, Tetsuhiro TANAKA, Sachiaki TEZUKA
  • Publication number: 20140203277
    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: Application
    Filed: January 16, 2014
    Publication date: July 24, 2014
    Applicant: Semiconductor Energy Laboratory Co., Ltd.
    Inventor: Akihisa SHIMOMURA
  • Patent number: 8772129
    Abstract: A manufacturing method of an SOI substrate which possesses a base substrate having low heat resistance and a very thin semiconductor layer having high planarity is demonstrated. The method includes: implanting hydrogen ions into a semiconductor substrate to form an ion implantation layer; bonding the semiconductor substrate and a base substrate such as a glass substrate, placing a bonding layer therebetween; heating the substrates bonded to each other to separate the semiconductor substrate from the base substrate, leaving a thin semiconductor layer over the base substrate; irradiating the surface of the thin semiconductor layer with laser light to improve the planarity and recover the crystallinity of the thin semiconductor layer; and thinning the thin semiconductor layer. This method allows the formation of an SOI substrate which has a single-crystalline semiconductor layer with a thickness of 100 nm or less over a base substrate.
    Type: Grant
    Filed: September 27, 2010
    Date of Patent: July 8, 2014
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Hidekazu Miyairi, Akihisa Shimomura, Tatsuya Mizoi, Eiji Higa, Yoji Nagano
  • 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: 8741740
    Abstract: An SOI substrate is manufactured by forming an embrittled layer in a bond substrate by increasing the dose of hydrogen ions in the formation of the embrittled layer to a value more than the dose of hydrogen ions of the lower limit for separation of the bond substrate, separating the bond substrate attached to the base substrate, forming an SOI substrate in which a single crystal semiconductor film is formed over the base substrate, and irradiating a surface of the single crystal semiconductor film with laser light.
    Type: Grant
    Filed: September 29, 2009
    Date of Patent: June 3, 2014
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Akihisa Shimomura, Hajime Tokunaga
  • Publication number: 20140116614
    Abstract: An object is to improve productivity related to a laser light irradiation step in a bonding technique of substrates using glass frit. A highly airtight sealing structure or a highly airtight light-emitting device, which can be manufactured with high productivity, is provided. When a glass layer by melting glass frit or a sintered body by sintering glass frit is irradiated with laser light, in order to increase the efficiency, a light-absorbing material is attached to a surface of the glass layer. The laser light irradiation is performed on the light-absorbing material and the glass layer. The substrates are fixed with the glass layer therebetween.
    Type: Application
    Filed: October 22, 2013
    Publication date: May 1, 2014
    Applicant: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Shuji Fukai, Yusuke Kubota, Mika Jikumaru, Takeshi Nishi, Akihisa Shimomura, Yoji Nagano, Daiki Nakamura
  • Publication number: 20140113440
    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: December 31, 2013
    Publication date: April 24, 2014
    Applicant: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Koichiro TANAKA, Hidekazu MIYAIRI, Aiko SHIGA, Akihisa SHIMOMURA, Atsuo ISOBE