Patents by Inventor Takahiro Kawashima

Takahiro Kawashima 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: 20150161968
    Abstract: A display device includes a display section including a light-emitting element and a drive transistor, and being configured to supply a current to the light-emitting element to cause the light-emitting element to emit light; a signal line driving circuit configured to supply a signal voltage applied between a gate and a source of the drive transistor; and a control circuit configured to: calculate an amount of threshold voltage shift of the drive transistor on the basis of an amount of deterioration of a threshold voltage of the drive transistor during a deterioration period in which the signal voltage is kept at a value that is not zero and an amount of recovery of the threshold voltage of the drive transistor during a recovery period in which the signal voltage is kept at zero; and correct the signal voltage in accordance with the amount of threshold voltage shift.
    Type: Application
    Filed: November 26, 2014
    Publication date: June 11, 2015
    Inventors: HIROSHI HAYASHI, TAKAHIRO KAWASHIMA
  • Patent number: 9048220
    Abstract: A method of crystallizing a silicon thin film, which enables uniforming the size of a crystalline grain of the silicon thin film, includes: a second process of stacking, on a substrate, a first gate electrode having a first reflectivity; a third process of stacking a second gate electrode on the first gate electrode, the second gate electrode having a second reflectivity lower than the first reflectivity and including a top face having an area smaller than an area of the top face of the first gate electrode; a fourth process of stacking a gate insulation film to cover a first region and a second region; a fifth process of stacking a noncrystalline silicon thin film on the stacked gate insulation film; and a sixth process of crystallizing the noncrystalline silicon thin film by irradiating the noncrystalline silicon thin film from above with a laser beam.
    Type: Grant
    Filed: September 9, 2011
    Date of Patent: June 2, 2015
    Assignee: JOLED INC.
    Inventors: Tomohiko Oda, Takahiro Kawashima
  • Patent number: 9000437
    Abstract: A thin-film semiconductor device according to the present disclosure includes: a substrate; a gate electrode formed above the substrate; a gate insulating film formed on the gate electrode; a channel layer that is formed of a polycrystalline semiconductor layer on the gate insulating film; an amorphous semiconductor layer formed on the channel layer and having a projecting shape in a surface; and a source electrode and a drain electrode that are formed above the amorphous semiconductor layer, and a first portion included in the amorphous semiconductor layer and located closer to the channel layer has a resistivity lower than a resistivity of a second portion included in the amorphous semiconductor layer and located closer to the source and drain electrodes.
    Type: Grant
    Filed: March 21, 2012
    Date of Patent: April 7, 2015
    Assignees: Panasonic Corporation, Panasonic Liquid Crystal Display Co., Ltd.
    Inventors: Hiroshi Hayashi, Takahiro Kawashima, Genshirou Kawachi
  • Publication number: 20150048810
    Abstract: A bidirectional DC-DC converter includes a series circuit of a first winding of a first reactor, a second reactor, and a first switch connected to both ends of a first DC power source, a series circuit of a second switch and a second DC power source connected to both ends of the first switch, a series circuit of a second winding of the first reactor, a third reactor, a first selector switch, and a first diode connected to both ends of a series circuit of the second reactor and the first switch, a series circuit of a second selector switch, a second diode, and the second DC power source connected to both ends of a series circuit of the first selector switch and first diode, and a controller turning on/off the switches and the selector switches.
    Type: Application
    Filed: January 24, 2013
    Publication date: February 19, 2015
    Applicants: Sanken Electric Co., Ltd., National University Corporation Shimane University
    Inventors: Hiromitsu Terui, Hideki ASUKE, Hideharu Takano, Masayoshi Yamamoto, Takahiro Kawashima
  • Publication number: 20150007745
    Abstract: A railcar door apparatus includes: a side sliding door that opens and closes an opening of a side bodyshell of a railcar; a first elastic member attached vertically to an end of the door; and a second elastic member opposed to the first so they do not touch when the door is closed. The first elastic member includes a first base portion and a first projecting wall portion projecting from the base toward the second elastic member; the second elastic member includes a second base portion and a second projecting wall portion projecting from the base toward the first elastic member; when the door is closed, a gap space is formed between the first and second elastic members, and the projecting wall portions overlap; and vertical grooves or projections are formed on the outside of at least one of the projecting wall portions, the outer surface facing the gap space.
    Type: Application
    Filed: December 3, 2012
    Publication date: January 8, 2015
    Applicant: KAWASAKI JUKOGYO KABUSHIKI KAISHA
    Inventors: Takahiro Kawashima, Tsunetoshi Goto, Hiroyuki Hirata
  • Patent number: 8912054
    Abstract: A method of manufacturing a thin-film semiconductor device according to the present disclosure includes: preparing a substrate; forming a gate electrode above the substrate; forming a first insulating film on the gate electrode; forming a semiconductor thin film that is to be a channel layer, on the first insulating film; forming a second insulating film on the semiconductor thin film; irradiating the second insulating film with a beam so as to increase a transmittance of the second insulating film; and forming a source electrode and a drain electrode above the channel layer.
    Type: Grant
    Filed: April 5, 2012
    Date of Patent: December 16, 2014
    Assignees: Panasonic Corporation, Panasonic Liquid Crystal Display Co., Ltd.
    Inventors: Hiroshi Hayashi, Takahiro Kawashima, Genshiro Kawashi
  • Patent number: 8907341
    Abstract: A thin-film semiconductor device includes a semiconductor device part and a capacitor part. The semiconductor device part includes: a light-transmitting first gate electrode; a light-shielding second gate electrode; a first insulating layer; a semiconductor layer; a second insulating layer; and a source electrode and a drain electrode. The capacitor part includes: a first capacitor electrode made of a light-transmitting conductive material; a dielectric layer; and a second capacitor electrode. The second gate electrode, the semiconductor layer, and the second insulating layer have outlines that are coincident with one another in a top view.
    Type: Grant
    Filed: December 11, 2012
    Date of Patent: December 9, 2014
    Assignee: Panasonic Corporation
    Inventors: Arinobu Kanegae, Takahiro Kawashima
  • Patent number: 8860037
    Abstract: A thin-film transistor device includes a gate electrode formed above a substrate, a gate insulating film formed on the gate electrode, a crystalline silicon thin film that is formed above the gate insulating film and has a channel region, an amorphous silicon thin film formed on the crystalline silicon thin film, and a source electrode and a drain electrode that are formed above the channel region, and the crystalline silicon thin film has a half-width of a Raman band corresponding to a phonon mode specific to the crystalline silicon thin film of 5.0 or more and less than 6.0 cm?1, and an average crystal grain size of about 50 nm or more and 300 nm or less.
    Type: Grant
    Filed: April 2, 2014
    Date of Patent: October 14, 2014
    Assignee: Panasonic Corporation
    Inventors: Takahiro Kawashima, Tomohiko Oda, Hikaru Nishitani
  • Patent number: 8841673
    Abstract: A thin-film transistor device includes: a gate electrode above a substrate; a gate insulating film on the gate electrode; a crystalline silicon thin film above the gate insulating film; a first semiconductor film above the crystalline silicon thin film; a pair of second semiconductor films above the first semiconductor film; a source electrode over one of the second semiconductor films; and a drain electrode over an other one of the second semiconductor films. The first semiconductor film is provided on the crystalline silicon thin film. A relationship ECP<EC1 is satisfied where ECP and EC1 denote energy levels at lower ends of conduction bands of the crystalline silicon thin film and the first semiconductor film, respectively.
    Type: Grant
    Filed: January 16, 2013
    Date of Patent: September 23, 2014
    Assignees: Panasonic Corporation, Panasonic Liquid Crystal Display Co., Ltd.
    Inventors: Arinobu Kanegae, Takahiro Kawashima, Hiroshi Hayashi, Genshirou Kawachi
  • Patent number: 8841678
    Abstract: A thin-film transistor device includes: a gate electrode above a substrate; a gate insulating film on the gate electrode; a crystalline silicon thin film including a channel region which is provided on the gate insulating film; semiconductor films on at least the channel region; an insulating film made of an organic material which is provided over the channel region and above the semiconductor films; a source electrode over at least an end portion of the insulating film; and a drain electrode over at least the other end portion of the insulating film and facing the source electrode. The semiconductor films include at least a first semiconductor film and a second semiconductor film provided on the first semiconductor film. A relationship ECP<EC1 is satisfied where ECP and EC1 denote energy levels at lower ends of conduction bands of the crystalline silicon thin film and the first semiconductor film, respectively.
    Type: Grant
    Filed: January 9, 2013
    Date of Patent: September 23, 2014
    Assignees: Panasonic Corporation, Panasonic Liquid Crystal Display Co., Ltd.
    Inventors: Arinobu Kanegae, Takahiro Kawashima, Hiroshi Hayashi, Genshirou Kawachi
  • Publication number: 20140231813
    Abstract: A thin-film device includes: a first device unit having a first gate electrode and a first crystalline silicon thin film located opposite to the first gate electrode; and a second device unit having a second gate electrode and a second crystalline silicon thin film located opposite to the second gate electrode. The first crystalline silicon thin film includes a strip-shaped first area and a second area smaller than the strip-shaped first area in average grain size. The first device unit has, as a channel, at least a part of the strip-shaped first area. The second silicon thin film includes a second crystalline area smaller than the strip-shaped first area in average grain size. The second device unit has the second crystalline area as a channel. The strip-shaped first area includes crystal grains in contact with the second area on each side of the strip-shaped first area.
    Type: Application
    Filed: September 26, 2012
    Publication date: August 21, 2014
    Applicant: PANASONIC CORPORATION
    Inventors: Tomohiko Oda, Takahiro Kawashima
  • Patent number: 8796692
    Abstract: A thin-film semiconductor device includes: a gate electrode; a channel layer; a first amorphous semiconductor layer; a channel protective layer; a pair of second amorphous semiconductor layers formed on side surfaces of the channel layer; and a pair of contact layers which contacts the side surfaces of the channel layer via the second amorphous semiconductor layers. The gate electrode, the channel layer, the first amorphous semiconductor layer, and the channel protective layer are stacked so as to have outlines that coincide with one another in a top view. The first amorphous semiconductor layer has a density of localized states higher than those of the second amorphous semiconductor layers. The second amorphous semiconductor layers have band gaps larger than that of the first amorphous semiconductor layer.
    Type: Grant
    Filed: October 23, 2012
    Date of Patent: August 5, 2014
    Assignee: Panasonic Corporation
    Inventors: Arinobu Kanegae, Takahiro Kawashima
  • Publication number: 20140209911
    Abstract: A thin-film transistor device includes a gate electrode formed above a substrate, a gate insulating film formed on the gate electrode, a crystalline silicon thin film that is formed above the gate insulating film and has a channel region, an amorphous silicon thin film formed on the crystalline silicon thin film, and a source electrode and a drain electrode that are formed above the channel region, and the crystalline silicon thin film has a half-width of a Raman band corresponding to a phonon mode specific to the crystalline silicon thin film of 5.0 or more and less than 6.0 cm?1, and an average crystal grain size of about 50 nm or more and 300 nm or less.
    Type: Application
    Filed: April 2, 2014
    Publication date: July 31, 2014
    Applicant: PANASONIC CORPORATION
    Inventors: Takahiro KAWASHIMA, Tomohiko ODA, Hikaru NISHITANI
  • Patent number: 8766260
    Abstract: A substrate; a gate electrode formed above the substrate; a gate insulating film formed above the gate electrode; a crystalline silicon semiconductor layer formed above the gate insulating film; an amorphous silicon semiconductor layer formed above the crystalline silicon semiconductor layer; an organic protective film made of an organic material and formed above the amorphous silicon semiconductor layer; and a source electrode and a drain electrode formed above the amorphous silicon semiconductor layer interposing the organic protective film are included, and a charge density of the negative carriers in the amorphous silicon semiconductor layer is at least 3×1011 cm?2.
    Type: Grant
    Filed: September 7, 2012
    Date of Patent: July 1, 2014
    Assignees: Panasonic Corporation, Panasonic Liquid Crystal Display Co., Ltd.
    Inventors: Yuji Kishida, Takahiro Kawashima, Arinobu Kanegae, Genshirou Kawashi
  • Publication number: 20140167049
    Abstract: A method of manufacturing a substrate having a thin film thereabove includes: forming a thin film above the substrate; and crystallizing at least a predetermined area of the silicon thin film into a crystallized area through relative scan of the silicon thin film which is performed while the thin film is being irradiated with a continuous wave light beam, wherein in the crystallizing, a projection of the light beam on the thin film has a major axis in a direction crossing a direction of the relative scan, and the formed crystallized area includes a strip-shaped first area extending in the direction crossing the direction of the relative scan and a second area adjacent to the strip-shaped first area, the strip-shaped first area including crystal grains having an average grain size larger than that of crystal grains in the second area.
    Type: Application
    Filed: February 24, 2014
    Publication date: June 19, 2014
    Applicant: PANASONIC CORPORATION
    Inventors: Tomohiko ODA, Takahiro KAWASHIMA
  • Publication number: 20140167165
    Abstract: A thin-film transistor includes: a gate electrode above a substrate; a gate insulating layer above the gate electrode; a semiconductor layer opposed to the gate electrode with the gate insulating layer therebetween; a protective layer above the semiconductor layer and comprising an organic material; and a source electrode and a drain electrode each of which has at least a portion located above the protective layer. The protective layer includes an altered layer which has at least a portion contacting the semiconductor layer, and which is generated by alteration of a surface layer of the protective layer in a region exposed from the source electrode and the drain electrode. A relational expression of Log10 Nt?0.0556?+16.86 is satisfied where Nt (cm?3) represents a defect density of the semiconductor layer and ? (°) represents a taper angle of an edge portion of the protective layer.
    Type: Application
    Filed: May 29, 2013
    Publication date: June 19, 2014
    Applicant: PANASONIC CORPORATION
    Inventors: Yuji Kishida, Eiichi Satoh, Takahiro Kawashima
  • Patent number: 8735233
    Abstract: A crystalline silicon thin film is formed by irradiating a silicon thin film with a laser beam. The laser beam is a continuous wave laser beam. An intensity distribution of the laser beam in a first region about a center of the intensity distribution is symmetric on an anterior side and a posterior side of the center. The intensity distribution in a second region about the center is asymmetric on the anterior side and the posterior side. The first region is from the maximum intensity of the laser beam at the center to an intensity half of the maximum intensity. The second region is at most equal to the half of the maximum intensity of the laser beam. In the second region, an integral intensity value on the posterior side is larger than on the anterior side.
    Type: Grant
    Filed: April 19, 2012
    Date of Patent: May 27, 2014
    Assignee: Panasonic Corporation
    Inventors: Tomohiko Oda, Takahiro Kawashima
  • Publication number: 20140054590
    Abstract: A thin-film semiconductor device includes: a gate electrode; a channel layer; a first amorphous semiconductor layer; a channel protective layer; a pair of second amorphous semiconductor layers formed on side surfaces of the channel layer; and a pair of contact layers which contacts the side surfaces of the channel layer via the second amorphous semiconductor layers. The gate electrode, the channel layer, the first amorphous semiconductor layer, and the channel protective layer are stacked so as to have outlines that coincide with one another in a top view. The first amorphous semiconductor layer has a density of localized states higher than those of the second amorphous semiconductor layers. The second amorphous semiconductor layers have band gaps larger than that of the first amorphous semiconductor layer.
    Type: Application
    Filed: October 23, 2012
    Publication date: February 27, 2014
    Applicant: PANASONIC CORPORATION
    Inventors: Arinobu Kanegae, Takahiro Kawashima
  • Publication number: 20130320339
    Abstract: A thin-film semiconductor device includes a gate electrode formed above a substrate; a gate insulating film formed to cover the gate electrode; a semiconductor layer formed above the gate insulating film and having a channel region; a channel protective layer formed above the semiconductor layer and containing an organic material which includes silicon, oxygen, and carbon; an interfacial layer which is formed in contact with the channel protective layer between the semiconductor layer and the channel protective layer, and which includes carbon as a major component, the carbon originating from the organic material; and a source electrode and a drain electrode which are electrically connected to the semiconductor layer.
    Type: Application
    Filed: February 27, 2012
    Publication date: December 5, 2013
    Applicants: PANASONIC LIQUID CRYSTAL DISPLAY CO., LTD., PANASONIC CORPORATION
    Inventors: Takahiro Kawashima, Hisao Nagai, Eiichi Satoh, Yuji Kishida, Genshiro Kawachi
  • Publication number: 20130299837
    Abstract: In a thin-film semiconductor device, a semiconductor layer has a bandgap energy of 1.6 eV or less, an insulating layer formed above the semiconductor layer includes: a first insulating layer region placed outside of a first contact opening and above one end of a gate electrode; a second insulating layer region placed outside of a second contact opening and above the other end of the gate electrode which opposes the one end; and a third insulating layer region being rectangular and placed between the first contact opening and the second contact opening.
    Type: Application
    Filed: July 12, 2013
    Publication date: November 14, 2013
    Inventors: Hiroshi HAYASHI, Takahiro KAWASHIMA, Genshiro KAWACHI